They may also have a shelf, built-in illumination, electrical outlets, or Ethernet ports.
They are designed to stand alone or to be grouped together, with or without common sides or walls.
The word carrel may also refer to a small, isolated "study room" in public libraries and on university campuses;[1] the room may have a lockable door, to which the user is granted the key on request.
Carrels typically contain a desk (not necessarily one described as above), shelving and a lamp.
[1] Carrels originated in monasteries to help contain the cacophony of roomfuls of monks reading aloud, as was the early practice.