It may be the simplest possible question, but what does the # (sharp) mean in the name of the C# and F# languages?
There is a theory that C# got its name (initially the language was called COOL – C-like Object Oriented Language ) because it would be the evolution of C++, and they continued the game of incrementing the name of C. So they made the C++++ language , but they stacked the two increment operators. Stacked they look like
I've seen other theories, such as the musical note, but this one seems to have been invented later to have a "better" story.
F# was named to indicate that it is functional C#, after all it uses .NET and follows a similar line to C# despite being heavily inspired by OCaml .
The fact is, this is just an interesting curiosity, the name is what it is.
There's a sensational talk showing the trajectory of .NET/C# and some behind the scenes.