These are films both professional and learning experiences that have been created in 48hrs for various festivals. How these types of festivals work: Your team learns what prompt, props, dialogue, etc (whatever the requirements are for the challenge), on one day. You spend the next 48 hours writing your script, filming your movie and editing it to turn in before time runs out.
These are great ways to network, test your skills, and have fun on sets in a fast paced setting.