PHP is a very versatile language, allowing for programmers to make applications according to their various tastes or styles. But one thing all programmers should maintain is the ability to comment effectively. In essence, commenting can save hours of time perusing code months down the road- and is often required by employers.

Comments aren't parsed by the PHP engine, so they are only visible to those who are viewing the original source code of the file. This is great for documenting what each code block does, all while keeping the casual visitor to a website oblivious to the extra comments present on the application they are using.

Unlike HTML comments, PHP comments aren't even visible in the source code of a website. HTML comments are visible to the general public, which can potentially lead to the stealing of code or may even help hackers exploit applications. PHP comments aren't output to the browser at all, so they are completely safe from prying eyes.

There are actually three operators that we may use to tell the PHP engine that we want to use a comment. Single inline comments can be used with the "//" and "#" operators. For multiple-line comments, we use "/*" and "*/" respectively to indicate what is a comment and what is actually PHP code. While the first two operators are synonymous, the last one discussed is the only one that can perform multiple line comments with relatively little work.

Unknown to most, PHP comments can also be used for more practical scenarios, such as troubleshooting. Expert programmers will find they have a problem with their application, and comment out different blocks of code to see what is causing the error. While it is usually in new code blocks, this method will indeed show that sometimes the problem is due to program code interacting wrong, which can in effect mean the problem is anywhere in the application.

Commenting in PHP is also great to use in selection structures, since PHP has long been known as a hard to scale language. Once files start getting big, it can be dizzying to try and remember which loops and selection structures go where, and what they do. By commenting out every closing bracket, and what it is in relation to, the problem is easily fixed. This is often mandatory for programmers who work for employers.

Closing Comments

PHP Comments are quite handy as we can see, more so than most would think. From troubleshooting to simple documentation, the three methods of commenting have a lot of use to the proper programmer. For more information on comments in PHP, and in other languages, check out more books, articles, and magazines for a more detailed guide in using them effectively.