Tutorials are very useful but they are only teach you basic stuff so if you are a newbie, there’s a high probability that you will run into problems because a learning article won’t tell you details about real life scenarios, optimization problems or solutions to common issues.
For all of these you need to read guidelines or “best practices” articles because that’s how you will be able to write efficient code.

HTML

 Best Practices for a Faster Web App with HTML5

Excerpt:

Tip 1: Use web storage in place of cookies

Tip 2: Use CSS Transitions instead of JavaScript animation

Tip 3: Use client-side databases instead of server roundtrips

 HTML5: Techniques for providing useful text alternatives

Excerpt: Text alternatives are a primary way of making visual information accessible, because they can be rendered through any sensory modality (for example, visual, auditory or tactile) to match the needs of the user. Providing text alternatives allows the information to be rendered in a variety of ways by a variety of user agents. For example, a person who cannot see a picture can have the text alternative read aloud using synthesized speech.

30 HTML Best Practices for Beginners

Excerpt: The most difficult aspect of running Nettuts+ is accounting for so many different skill levels. If we post too many advanced tutorials, our beginner audience won’t benefit. The same holds true for the opposite. We do our best, but always feel free to pipe in if you feel you’re being neglected. This site is for you, so speak up! With that said, today’s tutorial is specifically for those who are just diving into web development.

20 html best practices you should follow

Excerpt: Most of the web pages you encounter is presented to you via HTML, the world wide web’s markup language. In this article, I will share with you 20 best practices that will lead to clean and correct markup.

Five Best Practices for Mobile HTML5 Web App User Interaction Design

Excerpt: Organizations have options when developing mobile apps; the most significant choice is whether to develop native apps for specific phone OS’s (iOS, Android, Symbian) or to develop HTML5 web apps. Since native apps have more direct access to the phone’s hardware they can be more powerful, but there are also advantages to developing web apps. The biggest web app benefit is the ability to develop a single app that runs on multiple platforms. For many brands maintaining control of distribution is also critical.

 CSS

CSS3 Best Practices

Excerpt: Since CSS3 has become such a big deal in the future-thinking minds of web designers today, I think it would be appropriate for front-end developers to begin formulating some best-practice habits and techniques so that any CSS3 development we do is done right, and we therefore are able to get CSS3 development off to a good start.

30 CSS Best Practices for Beginners

Excerpt: CSS is a language that is used by nearly every developer at some point. While it’s a language that we sometimes take for granted, it is powerful and has many nuances that can help (or hurt) our designs. Here are thirty of the best CSS practices that will keep you writing solid CSS and avoiding some costly mistakes.

10 Best CSS Practices to Improve Your Code

Excerpt: It’s really easy to find yourself wondering how your CSS got to be such a mess.Sometimes it’s the result of sloppy coding from the start, sometimes it’s because of multiple hacks and changes over time.

9 CSS Best Practices You Need to Know

Excerpt: With just about everything, there are certain best practices that everyone should follow. With CSS, these are some rules that both beginners and experts need to consider, to style your website designs the right way.

CSS Standards & Best Practices

Excerpt: CSS is something that is extensively used on almost every site. Lets take some time to ensure that our stylesheets are built with some good standards. The below tips will really help CSS beginners a lot in development.

70 Expert Ideas For Better CSS Coding

Excerpt: CSS isn’t always easy to deal with. Depending on your skills and your experience, CSS coding can sometimes become a nightmare, particularly if you aren’t sure which selectors are actually being applied to document elements. An easy way to minimize the complexity of the code is as useful as not-so-well-known CSS attributes and properties you can use to create a semantically correct markup.

JavaScript/AJAX

10 Most Useful Java Best Practice Quotes for Java Developers

Excerpt:

Quote 1: Avoid creating unnecessary objects and always prefer to do Lazy Initialization;

Quote 2: Never make an instance fields of class public;

Quote 3: Always try to minimize Mutability of a class.

Best Practices on JavaScript and AJAX Performance

Excerpt: JavaScript can save your day or it can cause you nightmares. JavaScript and XHR (XmlHttpRequest) enable what the industry considers to be Web 2.0 – meaning highly interactive web sites where some application logic is pushed down to the client into the browsers JavaScript engine. As with any application code – regardless of the language and runtime environment – it is easy to not follow Best Practices which ultimately negatively impact the end-user experience with the site.

10 tricks that will make your jQuery enabled site go faster

Excerpt: During the last few weeks, I’ve had the chance to go more in depth with jQyery and general site performance. I’ve found some techniques that makes my site go much faster. I don’t know if they’re all best practice, but this article is meant to at least give you some good ideas.

14 Helpful jQuery Tricks, Notes, and Best Practices

Excerpt: If there is one bad thing about jQuery, it’s that the entry level is so amazingly low, that it tends to attract those who haven’t an ounce of JavaScript knowledge. Now, on one hand, this is fantastic. However, on the flip side, it also results in a smattering of, quite frankly, disgustingly bad code (some of which I wrote myself!). But that’s okay; frighteningly poor code that would even make your grandmother gasp is a rite of passage. The key is to climb over the hill, and that’s what we’ll discuss in today’s tutorial.

jQuery…Worst Practices

Excerpt: jQuery and Regular Expressions have a lot in common: They are both amazingly powerful and they are both as ugly as a knife fight between two obese street-whores in a garbage-strewn alley

24 JavaScript Best Practices for Beginners

Excerpt: As a follow-up to “30 HTML and CSS Best Practices”, this week, we’ll review JavaScript! Once you’ve reviewed the list, be sure to let us know what little tips you’ve come across!

Php/MySQL

63+ best practice to optimize PHP code performances

Excerpt: Today i am searching solutions for any tips and tricks about best practice to optimize PHP code performances and i found some of useful articles which you may interested with.

Top 20+ MySQL Best Practices

Excerpt: Database operations often tend to be the main bottleneck for most web applications today. It’s not only the DBA’s (database administrators) that have to worry about these performance issues. We as programmers need to do our part by structuring tables properly, writing optimized queries and better code. Here are some MySQL optimization techniques for programmers.

Ten PHP Best Practices Tips that will get you a job

Excerpt: I started watching the job boards, and a nice-looking full-time PHP position caught my eye, so I sent out a resume and landed an interview. Before the face-to-face portion, I chatted with the owner and head programmer on a conference call, and they ended up sending me a technical assessment quiz. One particular question caught my eye on this quiz… it looked something like this.

Best Practices: PHP Coding Style

Excerpt: One of PHP’s greatest strengths can also be a great weakness in the wrong hands. I’m talking about its forgiving nature. One of the reasons why PHP has become so wildly popular is because it lets very inexperienced web developers build powerful applications without much planning, consistency, or documentation. Unfortunately, that means an awful lot of PHP code out there is sloppy, hard to read and impossible to maintain.

PHP & MySQL Best Practices for Rock-Solid Applications

Excerpt: PHP and MySQL are often the preferred technologies for building web applications because they allow you to build robust web applications very rapidly. This rapid development, however, sometimes leads to code that is hard to maintain, doesn’t scale well or performs poorly.

10 Principles of the PHP Masters

Excerpt: With PHP’s widespread adoption,it’s almost too easy to find a script or snippet to do exactly what you need. Unfortunately, there’s no filter as to what is a “good practice” and what’s, well… not so good when writing a PHP script. We need trustworthy sources, who have proven they have a solid grasp on the best practices of PHP.

Common Security Flaws In PHP Applications

Excerpt: No matter how long you’ve been programming or scripting, once in a while you’ll catch yourself making a serious (security) flaw that you thought you’d never make, because you “have the experience“. Some of the most basic things a programmer should think of, but often forgets – because after all, we have to think of *a lot* of best-practice situations.

Misc

Best Practice: Backups

Excerpt: What if I told you to take your latest production backup, restore it on a different machine and try using the database? Are you comfortable with that task? Do you think it will work? When was the last time you tested your backups?

 Best Practices on Web Site Performance Optimization

Excerpt: Over the last couple of years performance of web applications became more important to businesses as search engines (such as Google) factor in performance into their ranking. This ultimately leads to Performance == Better Visibility == More Users == More Revenue.

Web Form Design Best Practices

Excerpt: Some of the topics I discuss and provide patterns for are: label alignment, required form filed, input field sizes, content grouping, primary & secondary actions, help text & tips, dynamic help systems, inline validation, error messages, progress indicators, success messaging, progressive disclosure, gradual engagement, tabbing, flexible data inputs, smart defaults, paths to completion, selection dependent inputs, and more…

Best Practice – The Git Development Cycle

Excerpt: Git is quite an awesome version control system. Why? Because it’s lightning fast, even for large projects (among other reasons). But, how do you use Git effectively for development on a daily basis?

When to Highlight Required Form Fields

Excerpt: Have you ever tried filling out a form and got distracted or confused by the red asterisks next to the form fields? Those asterisks are there to highlight which fields need filling out. This is a common practice found on many forms today that needs reconsidering.

Code review is a good investment

Excerpt: According to this article, it looks like testing is overrated !! Code review might be the way to go !

Let’s make the web faster – Google Code

Excerpt: PHP is a very popular scripting language, used on many popular sites across the web. In this article, we hope to help you to improve the performance of your PHP scripts with some changes that you can make very quickly and painlessly. Please keep in mind that your own performance gains may vary greatly, depending on which version of PHP you are running, your web server environment, and the complexity of your code.

Best Practices for Speeding Up Your Web Site

Excerpt: The Exceptional Performance team has identified a number of best practices for making web pages fast. The list includes 35 best practices divided into 7 categories.

 Web Accessibility Best Practices

Excerpt: The primary purpose of these HTML/XHTML Best Practices is to improve the accessibility of web resources at the University of Illinois at Urbana/Champaign for students, faculty, staff, and the general public.