what does pear stand for in php?

The PEAR stands for PHP Extension and Application Repository, or PEAR is a repository of 
 PHP software code. Stig S. Bakken founded the PEAR project in 1999 promoting the reuse of 
code that performs common tasks. The project explores to provide a structured library of code, to 
manage code packages and to maintain a system for distributing code, and to promote a standard 
coding style.

Although community-driven, the PEAR project consists of the PEAR group that serves as the 
governing body and takes care of administrative functions. Each PEAR code package consists of 
an independent project below the PEAR umbrella. It has its own, version-control and development 
team and documentation.

Related article - Applications of PHP Programming Language

PEAR packages

A Pear package is distributed as a gazetted tar file. Each archive consists of the source code written 
in PHP, usually in an object-oriented style. Numerous PEAR packages can promptly be utilized by 
developers as ordinary third party code via simple include statements in PHP. More elegantly, the 
PEAR package manager that comes with PHP by default can be used to install PEAR packages so 
that the additional functionality provided by the package appears as an integrated part of the  
PHP installation. Unlike the inclusive Perl Archive Network (CPAN) archives, which PEAR took as 
its model, PEAR packages do not have built-in dependencies, so that the placement of packages in 
the PEAR package tree is not related to code dependencies. Rather, PEAR packages must explicitly 
declare dependencies on other PEAR packages.

The PEAR base classes include code for simulating object-oriented consistent error-handling and 
destructors. Packages exist for some essential PHP functions including authentication, database 
access, caching, configuration, encryption, web services, HTML, and XML.

PEAR stands for "PHP Extension and Application Repository." It is a framework and delivery 
system for reusable PHP components. It extends PHP and gives a more level of programming for 
all web developers. PEAR is divided into three different classes: PEAR core components, PEAR 
package, and PECL package. 

PEAR package manager

The PEAR package manager gives a standardized method to install, uninstall, or upgrade with new 
PEAR packages or PECL extensions. Before installing a package it can also be instructed to take 
care of package dependencies so all the extra required packages are installed too.

The PEAR package manager is kept running from the command line using the pear command. 
Usually, it is in this way just the server administrator who can alter the installed base of PEAR and 
PECL extensions. On a PHP installation running on Linux, the PEAR Package Manager is ready for 
use by default, but on Windows, the PEAR Package Manager is available only after running a batch 
file called go-pear.bat.

PEAR2 Pyrus

There was an attempt to redesign and improve PEAR from the ground up with PHP for PHP 5.3 or 
newer. The PEAR2 Pyrus can be utilized to install packages from PEAR channels.  The last release 
is from March 2011 and its improvement may have been discontinued due to the popularity of 
Composer.

PEAR and Composer

With Composer there is an option accessible for managing packages for a PHP project. The 
composer also supports the installation of PEAR packages. Some people in the PHP community 
argue for the composer's side to replace PEAR.

PECL

The PHP Extension Community Library (PECL) is conceptually similar to PEAR, and in fact, 
PECL modules are installed with the PEAR Package Manager. PECL has C extensions to 
compile into PHP

As in C programs, PECL extensions run more accurately than PEAR packages. PECL includes 
modules for XML-parsing,  access to extra databases, mail-parsing, embedding Perl or Python in 
PHP scripts and for compiling PHP scripts. PECL extend from the PEAR Project in October 2003. 

PECL extensions are documented with standard extensions within the PHP manual, so there is no 
specific manual for PECL extensions. In addition, many extensions began their development cycle in 
PECL and ended up in Core (distributed PHP source) and in many cases the PECL versions became 
unmodified.

if you want to know more about PHP, then click this link PHP training in Chandigarh.