More than 75% of websites use PHP as the development language. The popularity of wordpress, phpmyadmin and other open source projects has brought a large number of long tail projects. user. However, they are generally installed but rarely updated. The picture below shows the current usage statistics of PHP.
What’s surprising is that the left half of this image represents a version of PHP that is no longer supported. PHP 5.2 was no longer maintained as of January 2011. That doesn't mean you can't use it, but it does mean that you won't be able to keep up with certain security updates. Some distributions will try to fix some bugs, but your PHP version seems a bit lackluster because, you are using outdated technology from 2006.
Where to start
No one chooses PHP 5.2 version anymore, but these things have already happened, but I am not writing this blog to complain about anything, let alone give you some upgrade guides. Usually they are using some hosting space that started in 2006. They have a "long-term support" version to avoid using newer versions, or they have no plans to upgrade yet. Or maybe there are really many reasons. However, good stuff awaits you in newer versions of PHP.
PHP 5.3 adds a lot of useful OOP features! For example: anonymous functions, SPL extensions not just iterators, and the fabulous DateTime extension have been integrated into PHP 5.3. Also added the extremely important E_DEPRECATED error reporting flag. It will remind you that features you are using now will not be available in the next version. If you are already using PHP 5.3, your future upgrade path will be smoother. If you have online programs running on an older version, I do not recommend upgrading.
PHP 5.4 has carried out a series of optimizations, which has faster execution efficiency and less memory usage. Below are the results of the benchmark tests.
No matter what traits you use, PHP 5.4 improves program performance and reduces hardware costs. Therefore, I recommend that you keep upgrading when using open source software.
PHP 5.5 is still in testing and is not suitable for production environments. Since PHP 5.3, the risks of upgrades and changes will be greatly reduced.
Future
To be honest, the future belongs to those who use PHP5.4 and above. Staying updated and regularly tracking new features and progress in the language are part of our daily routine. If you are already behind, I strongly recommend that you start an upgrade plan and upgrade to a newer version. The effort is worth it, after all, the program runs for many years.
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