Notes are written on the staff, which consists of five horizontal lines and the spaces in between. Two staves can be combined to create the grand staff which is a bass and a treble staff connected by a brace.
Multiple staves can also be connected by a bracket when representing multiple instruments playing together.
Leger lines and spaces are used to extend the staff upwards and downwards. Consider that the higher a note is placed on the staff, the higher its pitch or sound.
Grand staff with clefs, brace, and leger lines; multiple instruments with bracket: