In my own words, musical staff or stave is simply a surface or platform on which music is properly written (just like a notebook page, where words and sentences are written).
On this surface, there are five (5) horizontal lines, with four (4) spaces. But just like an empty page of a note book, these lines with spaces gives no information yet, unless when written on it.
Now, when we say 'musical staff and clefs', in relation to English Studies, it's like saying 'note books and writings '. Not until you pen down something on an empty page of a notebook, the page remains without information. So it is with music. A Music Staff gives no information without indicating the clefs on it.
A Clef, therefore, is a musical notation written on a staff, indicating the pitch of the notes following it.
Below is how a Musical Staff looks like:
___5__________________
___4__________________D
___3__________________C
___2__________________B
___1__________________A
From the diagram, the lines are numbered 1 - 5, from the bottom upwards, and the spaces A - D in the same order.
The rule is this: notes (words - in relation to English) are written from the bottom upwards (unlike in English Studies where words are written from the left side to the right side.
NOTE
What is even a musical note (notation)?
A note is a notation representing the "pitch" and duration of a musical sound.
Another name for 'note' is 'sound'. Remember, music could of course be as well considered as the art of sound.