After php 5.4. 5.5 and 5.6 this new mayor update came. The update comes with many new programming features, techniques and ways of writing code. Installing PHP 7 could be done in multiple ways.

To install it for a localhost development like WAMP or XAMPP either check for software updates from their end and see if they come with the new PHP 7, If not you could always download (opens new window) a new PHP version. Note that by now PHP 7.1.4 is already released in its early state. If you've downloaded the new version don't forget to implement it the right way so that you're able to use it. Doing this could be established by following the following tutorial for WAMP: tutorial (opens new window) and the following turorial for XAMPP: tutorial (opens new window)

Update a servers PHP version
If you have your own server to host your websites on updating PHP could be established in multiple different ways. From a sudo apt-get update && sudo apt-get upgrade command it could work. But a better way is to download the new package with for linux
sudo apt-get install python-software-properties software-properties-common
sudo LC_ALL=C.UTF-8 add-apt-repository ppa:ondrej/php
sudo apt-get update

When you've updated PHP you're able to use many new functions and features. Next to that there are also speed improvements that came with this update.

Now you only need to check if PHP-7 had been installed by running the following command:

php -v

The output should be something like this.

   PHP 7.1.2 (cli) (built: Feb 14 2017 21:38:43) ( ZTS MSVC14 (Visual C++ 2015) x86)
    Copyright (c) 1997-2017 The PHP Group
    Zend Engine v3.1.0, Copyright (c) 1998-2017 Zend Technologies

Detailed instructions on getting php-7 set up or installed.

Remarks

This section provides an overview of what php-7 is, and why a developer might want to use it.

It should also mention any large subjects within php-7, and link out to the related topics. Since the Documentation for php-7 is new, you may need to create initial versions of those related topics.