Each level has at least one checkpoint where your progress can be saved. To activate a checkpoint Mos must touch it. When Mos dies she respawns at the checkpoint and it is deactivated. But another checkpoint can be activate.

The earlier levels feature a lot more checkpoints while the the levels only have one or two. In Version 1.1 even more checkpoints was added to the early levels.

As of Version 1.2 sometimes Checkpoints don't work correctly.