Error guessing is a test method in software testing (an investigation conducted to provide information about the quality of the software) where a software tester's past experience and intuition are relied upon to find bugs in programs.
Software testing is an investigation conducted to provide stakeholders with information about the quality of the software product or service under test. In software testing, error guessing is a test method in which test cases used to find bugs in programs are established based on experience in prior testing. The scope of test cases usually rely on the software tester involved, who uses past experience and intuition to determine what situations commonly cause software failure, or may cause errors to appear. 
