Php 8 is safer than php 7.

PHP 8 demonstrated superior data handling and loading capabilities compared to its predecessors. In addition to high performance, you might also expect significant memory savings. The reason is that the internal data structures are highly optimized.
One of the most important reasons to upgrade your PHP version is security. It will be safer if your WordPress is running one of the latest versions of the scripting languages. It will keep your business safe from the latest vulnerabilities on the "market" and will also regularly fix security flaws, as well as major improvements in execution speed and performance.
PHP 8, the well-known programming language and base for your website or blog on WordPress, is available in its stable version. Or rather, they are still developing and optimizing some steps, but this month it will be ready to optimize the website performance.

Php 8 offers various new features.

PHP 8 was officially released to general availability on November 26, 2020.
This major new update brings a number of powerful improvements and features to the language, and we're excited to bring you the coolest changes that will allow us to write better code and build more effective app programs.
On November 26, 2020, PHP 8 was released, a new major release that introduced several new features, many of which were already implemented in versions 7.2, 7.3 and 7.4. The PHP 8 version is already available in Plesk on our cloud and on dedicated servers, from the Obsidian version 18.0.32. You need to upgrade to the latest version of Plesk to take full advantage of PHP 8.

Php 7 is backward compatible with php 5.

As with the main version, the developers of PHP 7 have overhauled the application, fixing some old problems and, consequently, eliminating some more outdated features. Therefore, for use with a CMS or a shop, it should be clarified whether the software version currently used is compatible with PHP 7. The current versions of the programs (such as WordPress, Drupal 8 or TYPO3) are already compatible and compatible with the version released For 3.5 in February 2016, Joomla will also be compatible with PHP 7. Those who have written their own PHP scripts can also find important information about the changes directly on PHP. If something goes wrong after switching to the new version, it is obviously easy to restore the old PHP version in the control panel.
In PHP 5, the last major "version" of the scripting language dates back to eleven years ago. However, PHP has continued to evolve and is one of the most popular scripting languages ​​on the Internet today. With PHP 7, all Hostpoint customers can immediately benefit from the fastest PHP ever. PHP 7 makes thousands of changes to lines of code while being leaner. Improved error handling, increased security for encryption functions and reduced storage space requirements ... these are just some of the new features as well as significantly improved performance. Those who want more details can find the in-depth documentation on the PHP page.

Whenever we consider migrating to a new version, compatibility is taken into consideration. Note that PHP 7 is not compatible with previous versions. The main thing to remember is that if you don't diligently maintain your WordPress software, some scripts, plugins, or themes may not be compatible with the specific version of PHP you will be using. Also, they may not work as expected. Also, the wrong version of PHP can damage your website in whole or in part. Of course, it's also possible that the plugins or theme code are completely dependent on previous versions. Ultimately, we can always try to upgrade and downgrade if something goes wrong.

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