Springtails: What are they? How do you care for them? How do you start your own culture?

Product Links:
BioDude Springtails: https://www.thebiodude.com/collection...
BioDude Clean Up Crew Packs: https://www.thebiodude.com/collection...
Josh's Frogs Springtail Culture: https://www.joshsfrogs.com/temperate...
Josh's Frogs Culture Kit: https://www.joshsfrogs.com/springtail...