catalyst and CE

Sorry, I do not understand the question.

Is "CE" the "Cisco Express" line of Cisco Switches, such as the Cisco Express 500 ? If so, then note that the Cisco Express switches are part of the Catalyst product line.

The "catalyst" product line name has been around for many years, and has included a number of very different models. Older Catalyst models used the CatOS operating system; newer Catalyst models use IOS.

Are you asking of the Catalyst models such as the 2960 use the same operating system as the Cisco Express 500? If that is your question, then the answer is that both models use IOS, so the structure of the commands is very similar, but they use different versions of IOS, and they have different "features" (permitted capabilities). It is a good philisophical question to ask whether the "IOS" for the major Catalyst switches (often still IOS 12.1) is -really- the same "IOS" as for the major routers (often now IOS 12.4).

I do not understand what you mean by "in which contest" ? Did you mean something about Cisco certification examinations? Or was "contest" a small spelling mistake and you meant "context" ??