In the context of computer programming , instrumentation refers to an ability to monitor or measure the level of a product's performance, to diagnose errors and to write trace information.  Programmers implement instrumentation in the form of code instructions that monitor specific components in a system (for example, instructions may output logging information to appear on screen). When an application contains instrumentation code, it can be managed using a management tool. Instrumentation is necessary to review the performance of the application. Instrumentation approaches can be of two types: Source instrumentation and binary instrumentation.