Microlearning breaks a topic into short units. A unit typically takes three to ten minutes and has one clear goal, for example being able to create an order or knowing three password rules.
The format suits a busy workday. It is easier to find five minutes than an hour, and short courses are completed more often.
Microlearning is not the same as chopping a long course into pieces. Each unit must stand on its own and make sense. Use the format for what needs to be remembered and used, and preferably combine it with repetition over time.