ELI5: Explain Like I'm 5

Microswimmer

Microswimmers are very very small robots, so small that you can't even see them with your eyes. They have special tools that allow them to swim through liquids. They are usually used to explore things in tiny places, like a clogged up pipe or an infection in the body. They can be programmed to do different tasks, like collect data, deliver medicine, or clean an area.