Guzzle, an extensible PHP HTTP client
PHP Curl Class makes it easy to send HTTP requests and integrate with web APIs
HTTPlug, the HTTP client abstraction for PHP
Unirest in PHP: Simplified, lightweight HTTP client library.
A developer-experience focused HTTP client, optimized for most common use cases.
Common HTTP Client implementations and tools for HTTPlug
Requests for PHP is a humble HTTP request library. It simplifies how you interact with other sites and takes away all your worries.
Simple handler system used to power clients and servers in PHP (this project is no longer used in Guzzle 6+)