Exploratory testing with charters

Exploratory testing means designing and running tests at the same time, using what you learn to choose what to try next. It is not random clicking. A charter gives each session a goal, such as "Explore checkout with expired and declined cards to discover how payment errors are handled".

A time box keeps the session to 45 to 90 minutes. During it you write short notes: what you tried, questions that came up, and bugs. Afterwards you talk it through with someone, which is called a debrief.

This finds the problems nobody wrote a test case for, and it is where experienced testers find most of their serious bugs. Practise on sites that are buggy on purpose, such as the-internet.