Language integration tools are used to integrate with other applications, which are developed using other software development languages, for example, Java, .Net, PHP, and Ruby, which are as follows:
Java and .Net: Using the Force.com SOAP API, you can integrate Java applications. It uses the standard WSDL and SOAP to fulfill the integration requirements.
PHP toolkit: This toolkit provides a way to integrate a PHP web application and the Force.com application using SOAP API. You can invoke SOAP API methods within the Force.com platform.
Force.com toolkit for Ruby: This toolkit allows you to integrate the Force.com application with Ruby. In this integration, you can directly manipulate Force.com data within the Ruby application.