Open QuickTime Player
Click File
Select New Movie Recording
Click the Record button
Choose the camera and microphone if needed
Click the Record button again to stop
Save the video file
Open Photo Booth
Click the Record Video button
Click the red record button
Click the stop button to finish
Save or export the video
Open Screen Recording in QuickTime Player
Click File
Select New Screen Recording
Click the Record button
Choose full screen or a selected portion
Click Stop in the menu bar to finish
Save the recording
Use the Screenshot toolbar
Press Shift + Command + 5
Select Record Entire Screen or Record Selected Portion
Click Record
Click Stop in the menu bar to finish
Save the recording