Security Testing-It is a type of functional testing according to ISTQB. Relation to detections of viruses and threats.Used to check if site is vulnerable to hacks etc.

Interoperability Testing- Evaluate capability of software product to interact with one or more component or systems.

Maintainence Testing-If a system that is deployed in live environment ,but later needs to be changed due to many reasons like Additional features, new Os ,Planned up grade etc. ,so the testing that is carried out when the system is in live environment is called maintenance testing .It involves retesting and regression testing. Usually done when system needs modifications or during migration from one Os to another.

Compatibility Testing-Is the system compatible with various other systems or not. Like various window types 7,8,10 etc. or web application is compatible with various versions of IE,chrome or Windows etc.

Usability Testing-Is the application user friendly. Can the user find things on the website easily.