What is a signature in musical terms?

Answer 1

There are 2 main types that I know of: time signature and key signature.

Time signature is at the start of a piece of music (although it can change in the piece) and tells you how many beats per bar (the top number) and what type of beats they are (the bottom number). i.e. 2/4.

The 2 on top means that there are 2 beats in a bar.

The 4 on the bottom tells you that they are crotchet beats. Other common numbers that you get on the bottom are 2 for minim beats and 8 for quaver beats. 8 can also be used for dotted crotchet beats if the top number can be divided by 3, i.e. 9/8 means 3 dotted crotchet beats per bar, 12/8 4 dotted crotchet beats, etc.

The other type of signature you get is key signature. The key signature looks like #s and bs at the start of the piece (called sharps and flats respectively). If there are none of these at the start or in the piece it is probably in C major or A minor. Sharps (#s) raise the pitch of a note by one semitone and flats (bs) lower the pitch of the note by one semitone. In a key signature (at the beginning) you get only flats or only sharps or none. The amount of sharps or flats (up to 7) determines the key you are playing in. Naturals cancel out the sharp or flat and take the note back to its normal pitch but are not used in key signatures. It looks a bit like this- ♮ - I hope that worked.

Order of sharps: F# C# G# D# A# E# B#

Order of flats: Bb Eb Ab Db Gb Cb Fb

I hope I haven't overcomplicated things for you. You could ask clarification if there's something you're not sure on.