Computable Analysis investigates computability on real numbers and related
One approach to Computable Analysis is Type Two Theory of Effectivity
TTE provides a computational framework for non-discrete spaces with
of the continuum.
Its basic tool are representations.
A representation equips the objects of a given space with ``names'',
which are infinite words.
Computations are performed on these names.
We discuss the property of admissibility as a well-behavedness criterion
for representations. Moreover we investigate and characterise the class
which have such an admissible representation.
This category turns out to have a remarkably rich structure.