Hello, I am currently using Time Machine to do backups on my Macbook. I'm not really interested in being able to restore my Mac back to a certain date I'm only concerned with backing up my hard drive contents. My question is: If I am doing backups weekly, can I just delete the previous week's backup after backing up tonight? I mean, tonight's backup will contain all of the same files that last week's did (including any new files and excluding any deleted files). Am I right, or do I need to keep all of my back ups? Thanks!