Record your browser tab: This option is perfect if you only want to show your viewers what's happening on one specific tab in Chrome. We use this option most when we want to record over a Google Slides presentation, for example.
Record your desktop: Use this option when you want to show your viewer something outside Chrome (like a PowerPoint) or if you think you'll switch between multiple tabs and/or programs.
Record your webcam: This option is perfect when you just want to speak directly to students, no screen involved.
Note: It's possible to capture the audio from a webpage or computer program (for example the audio from a YouTube video on screen). To do that, you'll need to enable tab audio (in a tab recording) or system audio (in a desktop recording). Both options are available under "Show More Options" before you begin a recording.