"giving signs with light"

Does anybody know how it is possible to understand a sign which is given by a lamp via turning it on and off?
could Morse language be transferred through this way or it is a different kind of language?

It is possible that Morse code could be communicated in such a way, often via a Morse flashlight (though a standard light can be used for the same purpose).

This is what I always see in the movies - the signals are in Morse code: en.wikipedia.org/wiki/Signal_lamp

Thank you. there is a game, Penumbra, which my friend is playing it and he can’t figure out the four-digit code transferred by light signals.