How to read musical notes: Time Signatures
Music usually has two numbers at the beginning, one on top of the other. This is called a time signature. The time signature indicates how many beats there are in a measure - the space between bar lines, as well as what the general pace (rhythm) of a song will be.
Bar lines are vertical lines that intersect the entire stave at regular intervals. The end of a piece of music is indicated by a double bar line.
The top number of a time signature indicates how many beats are in a measure. The bottom number indicates the type of note that makes up each beat.
There are also 2 other common things you might see where the time signature should be:
Common Time same as 4/4 time.