What word describes this?

[Borntobeamum]

BBC
ITV.
I need to know what the initials as a whole is.
I know BBC is British Broadcasting Corporation etc but what word describes the letters?

They are initialisms. They are sometimes incorrectly referred to as acronyms but a true acronym can be pronounced as a single word, like UNESCO or UNICEF.

Initialism.

Acronym?

When you use the first letter of each word.

Thank you so much x x x

Xpost, and I stand corrected!!