USE_SERIAL.println() vs. Serial.println()

Some sketches use USE_SERIAL.println(), some Serial.println().
I found infos about Serial, but not about USE_SERIAL.

I work with an ESP8266-12E.

Which one should I use, what is the difference and where can I find infos?

Thanx for supporting!

-Didix

Which one should I use

Whichever one works, and output the data you want.

what is the difference and where can I find infos?

No idea. Some context, like the code that uses USE_SERIAL, would be useful.

@Didix - thanks for your post (now deleted), but the onus is on you to provide examples (preferably the ones you're interested in), not make the rest of us go looking for them.

Does this help? #define USE_SERIAL Serial

AWOL:
@Didix - thanks for your post (now deleted), but the onus is on you to provide examples (preferably the ones you're interested in), not make the rest of us go looking for them.

Sory, I didn't mean to make you searching. I just wanted to demonstrate, that this was not only the invention of one single coder. There are that many occurencies that it seems to be a common pattern.

AWOL:
Does this help?

#define USE_SERIAL Serial

Again sorry, I was away from coding for many years and I didn't recognize that.
Now I have seen, that all the examples I was looking at are following that pattern.

However, why are they doing that?
Why don't they just use Serial?
Is USE_SERIAL a deprecated pattern that has been replaced by Serial?

Thanx, Didix

However, why are they doing that?
Why don't they just use Serial?

So that they (or you) could easily use, say, Serial1 or a software serial instance instead.

ok, thanx!