Video doesn't have to be recorded and played back in real time. These are three film-making techniques which slow down or speed up events, and two of them don't even need a video camera, only video editing software.
Slow motion video is shot at a higher frame rate and then played back at normal speed. For example, if you shoot an action sequence with a GoPro at 120fps and then play it back at 30fps, you still get smooth video but at one-quarter speed. Consumer DSLRs and compact system cameras can't match this, but most can now shoot at 60fps. If you play this back at 30fps, you get half-speed slow-motion.
Stop-motion video is really still images turned into video. It's how many kids' cartoons and puppet shows are made. The principle is that you shoot each frame of the video individually, then turn them into a video sequence. It's a lot of work. Let's say you want a video running at 30fps – that means for each second of video you need to shoot 30 stills. It requires patience, a controlled studio environment (usually) and the ability judge how much to move each object between frames.
Time-lapse video is an automated variant of stop-motion video. Here, the movement comes from the natural world itself, so all you need the camera to do is take pictures at set intervals – typically 1-5 seconds apart. Many high-end cameras now have time-lapse modes built in (they create the movie file in-camera) OR intervalometers which capture the frames automatically, leaving you to combine them in your own video editor. You can use time-lapse to record natural phenomena such as clouds, sunsets, speeded-up city traffic and night and so on.
