What is Zend Engine?
Zend Engine is used internally by PHP as a complier and runtime engine. PHP script is loaded into memory and compiled to form ZendOpcodes
Lets understand this in detail using following Architecture -
In the early days of PHP4 worked as follows:
- PHP script is loaded into memory by Zend engine and compiled into Zend opcodes.
- Opcodes (short for Operation codes), are low level binary instructions.
- These opcode is executed and HTML is generated for the same.
- This generated HTML is sent to client (browser).
- This opcode is flushed from memory after execution.
Today, There are various apps and techniques to help speed up this process. Lets see how Modern PHP Script work.