I've been closely monitoring the use of my hard drive in order to determine how much space I will need in my new Mac. When I go to "about this mac" and then click on "storage" it shows the breakdown of what's stored on my hard drive. In this breakdown there's a section called "backups" and it shows that it is taking up over 50gb. of storage on my drive. Does anybody know what this stands for? I use time machine but I thought that only took up space on an external drive. Thanks.