Garage Band 

This is a software that allows you to make music. Garage Band is a really simple and useful software that you can produce music on.    

In the screen shot above it shows you my music that I am producing to go in my film. The boxes that you see the beat that I have selected. Once you have selected a beat you can make it loop or customise it with another beat. The lines that you see going up and down is where you can make the beat fade in and out also making it louder. This is useful if you want a beat to come into the track slowly.

In the screen shot above it shows the beats that I have selected and the track and how I have faded the beat in and out. The blue box at the bottom is the beat enlarged so you can see that there is nothing overlapping or cut out. This also allows you to mix the beats if you want to because you can cut them and move them around.
I find that Garage Band is a really good and useful software.