  A basic concept of Type Two Theory of Effectivity (TTE) is the notion of an
admissibly represented space. Admissibly represented spaces are closely related
to qcb-spaces. The latter form a well-behaved subclass of topological spaces.
We give a survey of basic facts about Type Two Theory of Effectivity,
admissibly represented spaces, qcb-spaces and effective qcb-spaces. Moreover,
we discuss the relationship of qcb-spaces to other categories relevant to
Computable Analysis.
