Burp or Burp Suite is a graphical tool for testing Web application security. The tool is written in Java and developed by PortSwigger Security. The tool has two versions: a free version and a full version that can be purchased after a trial period (Professional Edition). The free version has significantly reduced functionality. It has been developed to provide a comprehensive solution for web application security checks. In addition to basic functionality, such as proxy server, scanner and intruder, the tool also contains more advanced options such as a spider, a repeater, a decoder, a comparison, an extender and a sequencer. The company behind Burp suite has also developed a mobile application containing similar tools compatible with iOS 8 and above.