cURL

cURL is a computer software project providing a library and a command-line tool that let you make HTTP requests in PHP. The name is a play on “Client for URLs”, originally with URL spelled in uppercase to make it obvious it deals with URLs. Basically the cURL project produces two products: libcurl and curl.

libcurl is a free and easy-to-use client-side URL transfer library that allows you to connect and communicate to many different types of servers with many different types of protocols. libcurl supports the http, https, ftp, gopher, telnet, dict, file, and ldap protocols. libcurl also supports HTTPS certificates, HTTP POST, HTTP PUT, FTP uploading, HTTP form based upload, proxies, cookies, and user+password authentication. These functions have been added in PHP 4.0.2.

curl is a command line tool for getting or sending files using URL syntax. Since curl uses libcurl, curl supports the same wide range of common Internet protocols that libcurl does.

cURL is included to the server requirements for the most of the eCommerce engines like: Opencart, Zencart, Magento, Prestashop, Woocommerce, Jigoshop, Virtuemart, osCommerce.