What is PHP 7?
PHP 7 is a major release of PHP programming language and is touted to be a revolution in the way web applications can be developed and delivered for mobile to enterprises and the cloud. This release is considered to be the most important change for PHP after the release of PHP 5 in 2004.

New Features
There are dozens of features added to PHP 7, the most significant ones are mentioned below −
Improved performance − Having PHPNG code merged in PHP7, it is twice as fast as PHP 5.
Lower Memory Consumption − Optimized PHP 7 utilizes lesser resource.
Scalar type declarations − Now parameter and return types can be enforced.
Consistent 64-bit support − Consistent support for 64-bit architecture machines.
The null coalescing operator− New null coalescing operator added.
Secure random number generator − Addition of new secure random number generator API.
Improved Exception hierarchy − Exception hierarchy is improved.
Many fatal errors converted to Exceptions − Range of exceptions is increased covering many fatal error converted as exceptions.
Deprecated SAPIs and extensions removed − Various old and unsupported SAPIs and extensions are removed from the latest version.
Return and Scalar Type Declarations − Support for return type and parameter type added.
Anonymous Classes − Support for anonymous added.
Zero cost asserts − Support for zero cost assert added.