What's the difference between «стереть» and «удалить»?

Question

Are these words interchangeable? I recently read something like

• она стёрла видео с телефона

would it sound weird if I replaced стёрла for удалила?

Answer 1

For deleting a file it's essentially the same. But, there are some verbal and formality differences:

• стереть is "to erase". Like that thing that remove pencil lines from the paper. It's also the less formal, colloquial one.
• удалить is "to remove". It's more broad, more formal. It also coinsides with the medical term, you could say удалить селезенку for "to remove the spleen".

To add more similar words, but much less in a "deleting a file" context:

• уничтожить is "to destroy", you don't really use it in conjecture with files.
• убрать is "to remove", also "to pick trash"
• выбросить is "to recycle"
• вытереть is "to wipe", might be used in the context of wiping a device, but is somewhat strange to my ear
• отформатировать is a loan from "to format [a drive]", has a bit of a different meaning technically.

Answer 2

"Удалить" is the formal, standardised term for the action of removing a file from computer storage. (Not very apposite for the context, by the way, but there you are).

However, "стереть" is a synonym, coming from the times when magnetic tape was used for audio and video recording and computer storage (maybe not so familiar technology for younger folks).

In the context of magnetic tape records the verb "стереть" was the standard. You could say then: "стереть запись" -- "to erase the recording"; "стереть кассету" -- "to erase/blank the cassette".