PEAR is the abbreviation for "PHP Extension and Application Repository", which is the PHP extension and application repository.
PEAR the PHP program development process common functions to write into class library, covering the page rendering, database access, file operations, data structure, caching operations, network protocols, WebService and many other aspects, users can download these libraries and appropriate to make some customizations to achieve their own needs. Avoid repeatedly inventing "wheels". The advent of PEAR greatly improves the efficiency and quality of development of PHP programs.
PECL is the abbreviation for "PHP Extension Community Library", or PHP extension.
PECL can be seen as an integral part of the pear, providing functionality similar to pear. The difference is that all of pear's extensions are written in pure PHP code, and users can use the extended code to include their own PHP files directly after downloading to the pear extension. PECL, which is developed using the C language, is often used to supplement some of the underlying features that are difficult to do with PHP, and often need to be recompiled or set in a configuration file before it can be used in the user's own code.
PHP Learning Summary: The most direct expression: Pear is the upper layer of PHP extension, pecl is the underlying PHP extension. They all provide ready-made functions or classes for specific applications.
PHP pecl and pear differences