What is a curator?[]
Merriam-Webster's website defines a curator as, "a person who is in charge of the things in a museum, zoo, etc."
Curators on Scratch[]
Users on Scratch can make (a) studio(s), which, a lot of the time are like clubs. The curators are like the members and they also can add projects to that studio's gallery. They can remove a project they added. A Front Page Curator gets to select the featured projects for the front page for two weeks. There's an application process for doing so and restrictions on the projects they may feature, such as not their own projects.
External references[]
http://www.merriam-webster.com/dictionary/curator
https://wiki.scratch.mit.edu/wiki/Studio#Curators