Breakpoints are source code markers used to trigger actions during a debugging session.
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Typically, the purpose behind setting a breakpoint is to suspend program execution to allow you to examine program data. However, WebStorm can use breakpoints as triggers for a variety of different actions. Breakpoints can be set at any time during the debugging process. Your breakpoints don't affect your source files directly, but the breakpoints and their settings are saved with your WebStorm project so you can reuse them across debugging sessions.