A janitor or custodian (called caretaker in British English, see American and British English differences) is a person who takes care of a building, such as a hospital, school, office building, or apartment block. Janitors are responsible primarily for cleaning, and often (though not always) some maintenance and security. Similar but more managerial duties (and usually not including cleaning, for example) are performed by a superintendent, often called building superintendent.
High School diploma or equivalent.
Most janitors and custodians work in an office setting, school, government building, warehouse, and factory. Most of the work is done indoors.