MemLab is a tool designed to analyze JavaScript heap memory and detect memory leaks in both browser environments and Node.js. It provides a straightforward way to define end-to-end (E2E) test scenarios. Users can create tests by writing JavaScript functions that simulate browser interactions, such as clicking buttons or navigating to different pages. For instance, the provided code snippet demonstrates how to set up a test that clicks on a "Hotels" text link on Google Maps and then closes the resulting pop-up. Running MemLab is done through the command line interface (CLI). Users can execute their custom scenarios with a simple command like `$ memlab run --scenario test.js`. The tool offers various memory analysis options, including checking for duplicated strings, unbound object growth, and unbound shape growth in the heap. Each analysis type has a specific command, such as `$ memlab analyze string` for string duplication and `$ memlab analyze unbound-object` for tracking unbound objects. The tool also includes a programming API for deeper analysis. Users can take heap snapshots and identify memory leaks with a few lines of code. By importing the MemLab API, you can define a scenario, take snapshots, and then call the `findLeaks` function to pinpoint issues. This API approach provides flexibility for developers looking to integrate memory leak detection into their testing frameworks.