PHP cURL is the PHP **Client URL Library** extension.

> PHP supports libcurl, a library created by Daniel Stenberg, that allows you to connect and communicate to many different types of servers with many different types of protocols.

libcurl currently supports the `http`, `https`, `ftp`, `gopher`, `telnet`, `dict`, `file`, and `ldap` protocols. libcurl also supports HTTPS certificates, HTTP POST, HTTP PUT, FTP uploading (this can also be done with PHP's ftp extension), HTTP form based upload, proxies, cookies, and user+password authentication.

The PHP manual includes Installing/Configuring, Requirements, Installation, Runtime Configuration, Resource Types, Predefined Constants, Examples, and cURL Functions such as `curl_init` — Initialize a cURL session, `curl_setopt` — Set an option for a cURL transfer, and `curl_exec` — Perform a cURL session.