Back-ups with Time Machine

Does anyone know how to make Time Machine only keep the most recent back-up, instead of continuing to fill up my back-up hard drive with endless copies of prior back-ups? Or is there some advantage to keeping all those back-ups?

Mike, the way TM works it makes a full backup once, the first time, then after that the only thing it backs up is what changed. That's called an incremental backup. So even with a tone of "backups" on the drive, it's not a huge space hog. For example, my main drive is about 350GB of data. After backing up for the past 18 months, my TM HD has used 800 GB, or less than three times the size of the drive it's backing up. So TM is not really a huge drive hog with endless copies. The only files "copied" are the changed files, which are generally not that much.

That said, if you really want to get rid of old TM backups, the only way to do that is through TM itself. But that is not fun.

If your drive gets full and you are sure you don't care about any of the historical data there (i.e., you will NEVER want an older version of what you have now), then you can simply turn off TM, reformat the drive to erase all the old backups and then turn TM on again and restart the backup process. The first backup will again be a full backup and then incremental after that.

Frankly, I wouldn't worry about it. TM will make room for itself on the drive by deleting older backups eventually. When you see that happening (you get a message) then you can decide what to do. Generally, for me, once it starts deleting old data I just go ahead and wipe it slick and start over. Or I get a new external, start TM to it and wait a few months until I'm sure I'll never need the old data and then wipe it slick. Murphy demands that 10 minutes after you erase the backup you'll need a file...

Welcome to the forum. I will try and answer your questions.

First lets clarify something. When you look at Time Machine backups your not actually looking ar endless copies of prior backups. The first backups contain the initial files for the backups. Subsequent backups contain links to the older files plus new files added since the last backup. Time Machine continues to use space until it fills the drive but takes measures to save space. See here for more info.

Here's the advantage of Time Machine compared to other backup methods. Let's suppose that over the last two weeks you've written The Great American Novel. Earlier this morning you discover that you want to use a paragraph you wrote on day one but have long since deleted from the document. You can go back to the backups for that day and restore the version of the document that has that paragraph.

Thank you both for replying. Now I understand TM. I really appreciate the response!