What language is decas?

"Decas" is not a recognized programming language. It's possible that it's a:

* Typo: Perhaps you meant "Delphi" or "C#", which are both popular programming languages.

* Nickname: Someone might have created a nickname for a particular language or technology.

* Uncommon language: There are many lesser-known programming languages out there.

If you can provide more context about where you encountered the term "Decas," I might be able to help you figure out what it refers to.