4 Things I Wish I Would Have Known When I Started My Software Development Career

My software development career began about 15 years ago.

But only in about the last 5 years did I really start to see a large boost in my software development career.

Here are some of the things I wish I would have known when I got started in the software development industry; things that would have made me more successful, much earlier, if I would have known them.

There is no “right way” in software development

I wasted a large amount of time, both in studying and arguing, early on in my career, falsely believing there was an absolute “right way” for many aspects of software development.

It turns out that just about everything I once thought was correct about software development at some point turned out to be wrong.

But more importantly, I found that very few things were black and white.  Almost every decision when writing code and developing software is based on the current circumstances.

I’ve talked before about how the religious adoption of a technology can be harmful to software developers, but this topic goes beyond just a technology.

It is also true that no best practice is universal.  Even highly charged topics like whether or not to unit test or whether agile or waterfall methodologies are best, do not have straightforward one-is-always-right answers.

In my career, I’ve wasted plenty of time on the “right way” road that led to nowhere instead of taking the “pragmatic” (practical) road, which would have carried me much further.

Reading a book cover-to-cover is not the best way to learn

When I first started wanting to grow my knowledge of programming and different technologies, I spent too much time reading technical books about a specific technology cover to cover.

There is nothing wrong with reading books, but often the choice of what book to read and what parts of it to read are very important.

For example, I remember reading a very large book on programming with Visual C++.  (I’m pretty sure it was an earlier version of this book.)  Anyway, the book was a good book with lots of information, but reading it cover to cover was not the best approach to learning Visual C++.

I would have learned and retained a lot more by skimming over the chapters of the book to get a broad understanding of what there was to know about Visual C++, then figuring out what things were most important to learn first.

I would have had much more success by sitting down and actually practicing the basics by trying to actually build something than just reading or going through examples in the book.  You don’t really learn a technology until you’ve solved real problems with it.

Learning particular technologies in-depth is a waste of time

Not only did I waste time by reading books cover to cover, but I also often chose to read the wrong books.

I had mistakenly believed that learning a particular technology inside-out would be a good way to advance my career.

I spent too much time reading books about very specific technologies like ASP.NET or Hibernate instead of reading more books like “Code Complete,” “Clean Code,” and “Agile Principles, Patterns And Practices in C#.” (All of these books, by the way, I recommend that you read, if you haven’t already.)

While it is important to know about the technology you are using, it isn’t important to be an absolute expert in that particular technology.  There isn’t much benefit to knowing the exact API call to make when you can just easily look it up when you need it.

Too many technologies that I spent a good amount of time learning about in depth, ended up either dying out or being technologies that I eventually abandoned myself.  Most of the knowledge about those specific technologies ended up representing a big waste of time.

I found that it was important to become an expert at whatever programming language that I was using at the time, because expertise in a particular programming language will usually last you a pretty long time; I definitely would have still spent time learning in depth about C++, C# and Java, but, I perhaps, spent a little too much time learning all the intricacies of C++, which isn’t benefiting me much now.

Community is extremely important in your software development career

Early in my career, I made the mistake of not really reaching out to the community for help and to 

I was always good about helping my coworkers and being social at the various jobs I held, but I never really reached much beyond my company.

I spent a large amount of time trying to make an investment in my career at a particular company at the expense of making an investment of my time in the software development communities that I was involved in.

I spent lots of time creating internal presentations on technologies or best practices that could have been spent creating content and material that could have served the community as a whole, as well as brought me recognition at my job.

I also made the mistake of not thinking that I had something valuable to contribute.

I talk to many beginning software developers now and sometimes I think they have much more to contribute to the community than us software developers that have been in the field for a long time, because they understand better the issues that other beginners are struggling with.

If I could do it over again, I would have made sure to be much more involved in conferences and user groups earlier in my career.  I would have started my blog much earlier and I would have used much of my learning time to create projects and resources that would be able to help others rather than just reading a book.

Always have a side project

Perhaps the biggest change I would have made that would have impacted my career the most would have been to cut out all the TV watching, Everquest and World of Warcraft playing I did earlier in my life and replace that time with work on a side project.

I’ve wasted a pretty sizable amount of time in my life doing things that were enjoyable, but didn’t produce any long term benefit for my life.

About 3-4 years ago, I pretty much cut out watching TV completely and now I hardly ever watch movies either.  TV and most movies are just a huge waste of time that you could be using to do something useful.  The same goes for video games for the most part, but at least with video games you are actively doing something not just absorbing useless information.

I’ll always love to play video games and I don’t think I’ll ever stop, but I do wish I would have spent a good deal of the time I spent playing video games and watching TV on a side project instead.

Sadly, the first real side project I actually took on was only about 3 years ago when I started creating my first Android application.

When you are working for someone else, it is really important to spend time working for yourself as well, otherwise you are building someone else’s empire while neglecting your own.

Not only did I learn a huge amount from the side projects I have taken on in the last few years, but I have benefited greatly from them.  In fact, one of those side projects, creating Pluralsight courses, is something I am doing pretty much full time now.

Putting everything I learned together

These are just a few of the things that I wish I had known when I first started my software development career, but there are many more and lots of other things that I did do right from the beginning.

I’m actually working on a top secret project to put all this information together to help developers boost their career and learn to market themselves.

If you want to be the first to be notified when this project gets officially launched, sign up here, and I’ll be sure to let you know.

What about you?

What are some of the things you wish you would have known when you started your software development career?  Let me know in the comments below.

Quick side note: if you are stopping here reading this post, you are probably the kind of developer that cares about your career.  I’m putting together a complete package full of information on how to really boost you software development career and increase your earning potential.  It is only available for preorder right now.  I’m only going to be selling it at this heavily discounted price for a short time.  I’ll also have some exclusive interview with famous software developers like Bob Martin, Jon Skeet, and Jeff Atwood sharing their secrets to their success.

10 Ways to Success in Competitive Examinations

How to Prepare for a Competitive Exam

Do you plan to take a competitive exam in the near future?

If so, this article will help you make a good strategic plan to prepare for your exam.

Governments, agencies, colleges, and other entities deluged with millions of candidates use examinations to find a way to pick from among them in a way that at least seems fair and objective. There's always a fair amount of luck involved in a mass examination, but there is also always plenty of preparation you can do.

In various countries and contexts, competitive written exams may test for reasoning ability; mathematical ability; reading and comprehension; writing ability; or the fundamental knowledge of a subject area. Interviews may test for knowledge of current events, general knowledge about the job or qualification one is applying for, the ability to give an account of one's past or future or talents, or the ability to say something sensible about a controversial or complicated issue.

Ten Tips on Preparing for an Examination

1. Make Sure This Test Is for You

Before investing time in preparing for an exam, decide whether the work is worth it. Study the exam announcement and ask questions if necessary. Make sure you meet requirements like:

• Educational level or experience needed to qualify to take the exam;
• Percentage of marks, or grade point average;
• Any maximum or minimum age limit that applies to your exam.

2. Go Back to Your Fundamentals

Once you know you qualify for your exam, your next step should be to decide how to brush up on fundamentals you haven't practiced recently. Depending on the test, this may be math fundamentals you last looked at in grade school, principles of grammar, or the fundamentals of your science or engineering discipline. Dig out your old textbooks and put them where you can see them.

3. Get Up to Date

If it's applicable to your test, as it is in the Indian Civil Service, work on your general knowledge and keep it updated. You will want to be ready to discuss the current events that affect the government, school, or bureaucracy you aim to join. If you don't already, take a daily look at news media on current events.

4. Consider Paying for Coaching ("Joint Coaching Institutes")

You don't have to pay a company or institute for competitive examination preparation. Many do well without such coaching. But the right test preparation agency can offer you:

• counseling
• reassurance
• study materials with which to structure your time

Do investigate your chosen agency, and make sure it's not a scam; there are scammers out there.

5. Set Realistic Goals

Consider how much time you have until the test date, and how many other things you want to do in life—including fun things. Consider your level of ability, and the resources you have. Then set realistic, modest, and achievable goals and deadlines for finishing the different steps of your preparation. Manage your time so that your preparation includes each section of the test, with more time allotted to sections where you think you may be weaker.

6. Create a Support Group

Create a circle of friends who are interested in preparing for the same or similar examination. It will be very helpful in keeping up your morale. It will remind you that you are not struggling alone with an arbitrary, zero-sum world; many other people long for success, just like you do (see the numerous comments below). Though you may not all succeed the first time, you can at least support each other without hurting your own chances.

7. Be Positive

You should be positive and have faith in yourself. There is no guarantee that you will pass any exam on the first attempt, though there is no reason to assume you will fail. Be patient and support yourself over the long haul.

8. Take Mock Tests

It may not be difficult to answer all the questions on a test, but it's generally very difficult to answer them all in the allotted time. Obtain sample written tests from previous test occasions and time yourself as you take them. Understand how they are scored: whether it's to your advantage to guess at answers you aren't sure of, or whether you should skip these questions. Understand how fast you have to work to answer every question that has a chance of increasing your score. This kind of practice is very helpful.

9. Do Mock Interviews

Find sample interview questions (for example, in the library, in magazines, on the web) and write them down on cards, along with any other questions you can think of. Get your family or study group together, hand them the cards, and have them ask you the questions. It feels reassuring to be able to come up with something to say, even though it may not be perfect. Remember that it's quite likely you may be asked a question you don't know the answer to. If so, you can admit it; it's better not to guess or make something up. No one knows everything and there is no need to pretend to.

10. Go Easy on Yourself

Stay healthy while you prepare. Regular exercise and yoga boost your mental as well as physical strength. Do fun things during your study period, including on the night before the test. By that point, your preparation will be done--all except for showing up at the test, which is important in itself. Instead of trying to cram more information into your brain that night, why not watch a silly movie, or walk somewhere? Then, after arranging for your transportation and your breakfast, gathering up any documents or tools you need to bring, and laying out the clothes you plan to wear, go to sleep with a clear conscience. The result of the test will be out of your hands; you will have done all that you can do.

9 Scientific Study Skills to Ace Competitive Entrance Exams

It is Surprising that during 14 years of school studies, we are never taught how to study effectively. Every day, new research is being conducted on education, teaching skills and learning methods which we can use to learn scientific ways for note taking, textbook reading, memorizing and effective reviewing. We offer you 12 scientific study skills that can help you get sure-shot success in any competitive entrance exam. Use these hacks while preparing for JEE Main, IIT JEE Advanced, AIPMT, AIIMS, BITSAT and other competitive exams.

1.Get into the right mood like Pavlov’s dog

Classical conditioning experiment by Pavlov made dogs salivate as soon as they heard the bell ring – in anticipation of food. If you study the same subject at same time and same place, your brain makes the association and gets trained accordingly. Later on, you just have to follow the clock to the place, and you will automatically get in the mood to study the subject within 10 minutes. Works like a charm for subjects you hate or dislike!

2. Shorter study sessions work better than marathon sessions

Psychologists have found that students learn as much in one-hour sessions spread over four days as they learn in one six-hour marathon session. It means that students could cut their study time by at least 30% by using a well-planned study schedule or time table. When you study for less time, imposed time restriction makes your brain work more efficiently. Most of the askIITians report that they are able to cram much more a day before exam than a regular day – which just confirms this particular research conclusion. Besides, it is believed that during study breaks, mind works to absorb whatever you have learned automatically, without any conscious effort on your part. Hence, for intense memorization sessions like when you are trying to learn dates and events, names of countries and their capitals, a foreign language or math formulae, you should not study for more than 20 to 30 minutes at a stretch.

3. Sync your school timetable and home study schedule

When a teacher covers a topic in class, students should study it as soon as they can after coming from school, revise the topic and prepare revision notes. When there is a test in class, use the time before school to quickly memorize questions, brush up facts and learn diagrams.

4. Smart work is better than hard work

It is a maxim often used in corporate offices. Of course, it is applicable to students too. Attention you pay to the subject and alertness of your mind while studying matters more than the time you spend on it. Most common strategies to keep yourself alert are:

• Minimize distractions. 2-3 hours of studying in a quiet place without any disturbance is better than 10 years of studying with noise of TV blaring somewhere in the room, running errands in between studies, and people shouting in your ears. Of course, you cannot control all your family but you may adjust your time table to study early in morning or late at night when everyone else is quiet.
• You can start with the most difficult or boring subject when you are fully alert and pick up an easier or most interesting one when you are feeling down.
• Take 10-minute breaks between subjects to re-orient your brain and reward yourself for work well done. If you really feel like taking a break, take one. Do not waste time watching clock to take the break.

5. Do not study when you are sleepy

Everybody has a particular time when one is too sleepy to study anything. Sitting with books during that time is a total waste of time. For me, 3 pm is the time when I get quite slothful – about two hours after I have lunch. For some others, early morning is the time when they just can’t wake up to read anything coherently. If you have too much backlog to cover, just do something light at the time – like clearing your desk, sorting your notes or arranging your school bag to let the phase pass.

6. Do not schedule similar subjects one after another

If there is not enough space between radio waves, you get interference. Similarly, brain waves need to be spaced out too. It has been found that it is better put contrasting subjects one after another rather than clubbing similar subjects together. It means that studying Physics after Mathematics might not be a good idea. You can sandwich History or English Literature in between and your brain will able to absorb all three subjects much better.

7. Note taking in class

When you jot down lecture notes in class, underline the ideas that he says are important. Mark the ideas that the teacher says will be discussed later in detail with a ‘*’. Also write down common mistakes you teacher tells you about as ‘#-points’. Write sentences that start with ‘therefore’ and ‘in essence’ in a separate line as they are often the summary of what has been taught in class. Examples given by teachers are often most important for school exams. In subjects like Math, teacher’s examples are often most important. Writing down notes in the last few minutes of class is often a speed game. As teachers run out of time, they pack most content in last 5-10 minutes of class. You may have to keep writing after the class finishes jotting down everything.

8. Textbook reading method that actually works – OK4R

Dr. Walter Pauk has devised the OK4R method, which can help you pack more information through power reading. Here is how you go about it:

• O for Overview: In the first glance, just read the headings, sub-headings, introductory paragraph, and summary at the end of the chapter. It will give you general idea of what is included in the chapter.
• K for Key ideas: Now, go back to the beginning of the chapter and try to skim through the key ideas. First sentence of each paragraph, italics and bold-type text, tables, pictures and diagrams, bulleted sections and itemizations often present key ideas of the chapter. Try to comprehend them quickly.
• R1 for Reading the topic or chapter from beginning to end: Now that you already know what is being discussed, read through the entire chapter and see full explanation of the ideas that have been presented and how they have been explained.
• R2 for Recall: Now put your book aside and write down major points of what you have read and make your notes in few words or sentences. Immediate recall will only take a minute or two but doubles up retention time of the topic you are studying. Make notes as suggested using the ‘best note making system’ as suggested below.
• R3 for Reflect: Now that you have kept the material in the storage unit of your memory it, sift it to put it in your permanent memory. Think over it and try to find significance of what you have read and its relationship with other topics you have learnt.
• R4 for Review or Revision: On weekends, you can test yourself on what you have learned throughout the week. In schools, there can be tests and quizzes that help you go through your notes again. These time-to-time reviews or revisions help you to fix the information forever.

9. Color your books

As opposed to the popular idea, neat books don’t always mean that you are a good student. They also show that books may be ‘unused’. You can colour main ideas in red, dates and numbers in blue and supporting facts in yellow. Also mark circles, stars, boxes, and hash in margins, wherever needed, to make revisions easier. But colour your personal books only. Otherwise, library will ban you and your friends will never loan a book to you again.

Credits: This blog is brought to you by AskIITians.com.

Disclaimer: Toppr.com is not responsible for the accuracy, completeness, suitability, or validity of any information in this article. All information is provided on an as-is basis. Toppr does not assume any responsibility or liability for the information, facts or opinions appearing in the article.

10. Refresh button: Relax and take breaks during your hectic study timetable. Use this time to rejuvenate yourself, watch a movie, listen to some songs, or play a sport. This will help you to stay focused and feel fresh.

Tips To Crack Any Competitive Exam

The season of competitive exams is around the corner and we know you are doing all you can to crack these exams. These exams are designed to check your knowledge in particular sections. In this post we have tried to give you some important tips to crack any competitive exam, be it SSC, IBPS, Insurance, NDA, etc.

Plan Smartly – Once you have made up your mind to prepare for a competitive exam or to enter a particular sector, the most important thing is to plan your way. Get a rough idea when these exams are conducted in a given year and calculate how much time is with you for your preparation.

In all the competitive exam what is required essentially is your presence of mind. Studying till the last moment will only lead to stress and exhaustion. Before formulating your preparation strategy, chalk out the syllabus and measure your comfort level in individual section. Suppose you feel you are not good in reasoning or essay writing, divide your time table according to it and give extra time to these.

Make a list – Once you have a sense of the syllabus, make a list of the books or study material you would be requiring for the exam. Study material for the areas like Verbal Abilities, Math and English should be collected.

Break-up of time – Make a daily time table and do not forget to include your recreational activities in it. Also try to shuffle the subjects so that you do not get bored. You should try studying for at least 4 hours a day. Take time out for reading newspaper daily. 30 minutes for this would be sufficient, this will certainly help you prepare for your general awareness section.

Prepare notes – Whatever you study, try maintaining a notebook for it. Go through this notebook at the time of revision.

Set a finishing date – Set a finish date on your mobile, calendar or put it on your table. By this date you should finish learning new concepts. It is important that you stick to this date. After this you can start applying what you have learnt and see your performance by giving mock tests, practice previous year papers etc.

Quantitative Aptitude – Quantitative Aptitude should be given utmost importance at the time of preparation. Try practising questions daily. Go through the concepts first and then solve problems. Make a note of important formulas, theories and corollaries. You should be thorough with tables, square roots and cube roots to do calculations quickly. Quantitative questions are not difficult to solve, all you need is practise and speed to excel in this section. Find out more on how to excel in quantitative aptitude section.

Enrich your Vocabulary – Improving your vocabulary will help you a great deal in your English section. Questions on Synonyms, Antonyms and One word substitution will become an easy nut to crack. This is the part which is not given due importance by students. Having a good vocabulary will do you no harm instead it will also help you in your Group Discussion and Interview round ( only if you wish to sweep others by your command on language and some flowery words :) ).

Reasoning- Practice questions on age, direction and distance, seating arrangement and Venn diagram. They are almost asked in every competitive exam. You should also work on your speed. Try learning or making your own short cuts to solved a particular set of question. This is the part where you can not cram anything. All you need to do is to apply your brain and get done with the question and that isn’t a difficult task. Check out more tips on how to prepare for reasoning section, follow the link.

We are hopeful that this post will benefit you in a lot of way. These tips are specially designed to give you an extra edge and confidence needed for any competitive exam.

PREPARING FOR INTERVIEWS

    In interviews, your job is to convince a recruiter that you have the skills, knowledge and experience for the job. Show motivation and convince a recruiter that you fit the organization's culture and job description, and you get that much closer to an offer. 

7-Step Interview Prep Plan

1. Research the organization.

This will help you answer questions — and stand out from less-prepared candidates.

• Seek background information. 
  • Use tools like Vault, Wetfeet, CareerSearch or The Riley Guide for an overview of the organization and its industry profile.
  • Visit the organization’s website to ensure that you understand the breadth of what they do.
  • Review the organization's background and mission statement.
  • Assess their products, services and client-base.
  • Read recent press releases for insight on projected growth and stability.
• Get perspective. Review trade or business publications. Seek perspective and a glimpse into their industry standing.
• Develop a question list. Prepare to ask about the organization or position based on your research.

2. Compare your skills and qualifications to the job requirements.

• Analyze the job description. Outline the knowledge, skills and abilities required.
• Examine the hierarchy. Determine where the position fits within the organization.
• Look side-by-side. Compare what the employer is seeking to your qualifications.

3. Prepare responses.

Most interviews involve a combination of resume-based, behavioral and case questions. We encourage you to meet with us to practice telling your story in the best possible way.

4. Plan what to wear.

• Go neutral. Conservative business attire, such as a neutral-colored suit and professional shoes, is best.
• Err formal. If instructed to dress “business casual,” use good judgment.
• Plug in that iron. Make sure your clothes are neat and wrinkle-free.
• Dress to impress. Be sure that your overall appearance is neat and clean.

5. Plan what to bring.

• Extra copies of your resume on quality paper
• A notepad or professional binder and pen
• A list of references
• Information you might need to complete an application
• A portfolio with samples of your work, if relevant

6. Pay attention to non-verbal communication.

• Be mindful. Nonverbal communication speaks volumes. 
• Start ahead. Remember that waiting room behaviors may be reported.
• Project confidence. Smile, establish eye contact and use a firm handshake.
• Posture counts. Sit up straight yet comfortably. Be aware of nervous gestures such as foot-tapping.
• Be attentive.  Don't stare, but maintain good eye contact, while addressing all aspects of an interviewer's questions.
• Respect their space. Do not place anything on their desk.
• Manage reactions. Facial expressions provide clues to your feelings. Manage how you react, and project a positive image.

7. Follow up.

Many interviews end with “Do you have any questions?” 

• Bring a list. You may say, “In preparing for today's meeting, I took some time to jot down a few questions. Please allow me to review my notes.” 
• Be strategic. Cover information not discussed or clarify a previous topic — do not ask for information that can be found on the organization’s website.
• In your opinion, what makes this organization a great place to work?
• What do you consider the most important criteria for success in this job?
• Tell me about the organization’s culture.
• How will my performance be evaluated?
• What are the opportunities for advancement?
• What are the next steps in the hiring process?

Can DNA predict a face?

Florida police are searching for a man who lurks in the shadows.

For more than two years, he has terrorized at least a dozen women, peeping into windows and slipping into bedrooms to watch them sleep. He has touched several women’s feet or hair — some, he has sexually assaulted.

The media dubbed him the “Serial Creeper,” and police are desperate to find him. In September, theyreleased a sketch of a dark-haired, dark-eyed Latino man with smooth skin, high cheekbones and a pointed chin. But the sketch wasn’t drawn by a police artist based on eyewitness accounts. The Creeper has kept his face covered in every assault, says Kelly Denham, a police officer in Coral Gables, Fla. “He’s never been seen.”

So local police had to pursue a less-conventional route: They bought a computer-generated image based on the Creeper’s DNA.

For $4,500, a company based in Reston, Va., called Parabon NanoLabs analyzed DNA that the Creeper left behind at crime scenes. The analysis zeroed in on genetic clues linked to hair color, eye color, facial features and ancestry. Then, Parabon crafted a digital mash-up of the Creeper’s face.

The images Parabon creates don’t offer an exact picture of a suspect, says Ellen Greytak, Parabon’s bioinformatics director. “We work with law enforcement to give them an idea of who they should be looking for,” she says — or which people to cross off the suspect list.

In the last few years, several scientists and companies have ventured into the new world of appearance prediction. It’s a hazy place, where the roots of a person’s looks hide out in their genetic instruction books. Scientists dig up these roots by linking people’s physical features with tiny landmarks in their DNA. If investigators could use DNA to predict nose width, say, or eye size, they might have an easier time tracking down criminals.

Proponents say the technology can do more than give investigators a lead in a case. It could also help put a face to ancient people — long-lost ancestors, or perhaps even Neandertals. Some even imagine giving parents-to-be a glimpse at their unborn child’s visage, though that’s still a far-off dream.

In truth, the science for conjuring a person’s appearance from DNA remains a little skimpy. Facial features may be shaped by hundreds or thousands of genes — each with very tiny effects.

And scientists have only just begun to sort it all out. Hair, eye and skin color, as well as ethnic background, are relatively easy to pin down. But the genetic roots of other traits, such as height and face shape, are scattered throughout people’s DNA like dandelion seeds in the wind. It’s hard to track down every wispy speck. That’s why some researchers think current prediction attempts aren’t ready for prime time.

Some attempts rely mostly on genetic information about sex and ancestry (whether a person is male and of European descent, for example) to construct an image of someone’s face, says Manfred Kayser, a geneticist at Erasmus University Medical Center in Rotterdam, the Netherlands. And that, he says, “is not much more accurate than using your imagination.”

The face of a king

Until recently, the face of one of England’s most notorious kings was left to artists’ imaginations.

Known for his twisted spine and villainous ways, King Richard III probably had brown hair and dark eyes. Or maybe light hair and blue eyes — portraits painted after his death varied. But now, DNA has given scientists a better picture.

In 2012, more than 500 years after Richard was cut down in battle, archaeologists dug up the monarch’s yellowed skeleton under a parking lot in England (SN: 3/9/13, p. 14). Analyses of dozens of genetic clues from the DNA in his ancient bones finally offeredsolid details about Richard’s appearance, Kayser and colleagues reported last year in Nature Communications (SN Online: 12/2/14).

“Quite certainly he had blue eyes,” Kayser says. “And it’s very likely that he was blond as a kid and either blond or light brown as an adult.”

Kayser and colleagues knew what to look for because they and other scientists have tracked down genes controlling hair and eye color. The researchers first had to scan the genetic instruction books of thousands of people.

Each person’s instruction book, or genome, holds 3 billion chemical base pairs, DNA “letters” that spell out the plans for everything from sex to skin color. Most of those letters don’t vary much from person to person. But scientists can use slight changes in the text, one-letter differences called single nucleotide polymorphisms, to predict certain physical features.

Kayser’s team can, for example, deduce a person’s eye color by looking at just six letters spread out over six genes. To figure out hair color, the researchers focus on 22 letters. For blue or brown eyes, the team’s predictions are more than 90 percent accurate. Hair color is almost as good, with accuracies ranging from about 80 to more than 90 percent — pointing out a redhead is the easiest.

The team has used its system, called HIrisPlex, on DNA from King Richard’s bones. The system has crime-fighting appeal as well. It can pick out a person’s hair and eye color from blood, semen and saliva — even when DNA in the samples has broken down, the researchers reported last year in Forensic Science International: Genetics. That’s a big deal because forensic DNA can get shabby. If samples sit around too long at crime scenes, DNA can fall to pieces, becoming hard to analyze.

With hair and eye color in hand, Kayser’s team has now added skin color to its system, the team reported in September at the International Society for Forensic Genetics meeting in Krakow, Poland. Preliminary results suggest that the skin-color test is about as accurate as the tests for eye and hair color.

Clues about coloring are a good start for estimating appearance, but prediction tools are still rough around the edges. Eye colors other than blue and brown are difficult to predict, and DNA can’t distinguish between blond adults and brunet adults who were blond as children, for example.