Sally Greer asks:
Can I delete my downloads? They are getting massive, and since I was PC user before, I don't know the rules of the Downloads folder.
This may seem like a simple question to many readers, but I find folks who are new computer users or new to Mac get tripped up on the things that old Mac hands already know.
Every OS X user's home folder contains a Downloads folder, in which Safari and other browsers preferentially drop files you download. I recommend pruning this folder regularly, as it can wind up becoming massive over time as subsequent versions of a piece of software download into.
If you have a large enough drive, you might not care about deletion. But it does impose a burden on your backups. Even though an inert downloaded file only needs to be stored once with any software or service that creates a base set of files and then incremental differences later — including Time Machine — it still occupies space. For online backups, it's more you're uploading and storing remotely.
I'd argue that if you don't need a file after installing software, delete it, and empty the trash. If you do, copy it elsewhere so that you know it's available. Most software you purchase can be downloaded fresh, or a full copy is downloaded with each update. I recently found several different downloaded versions of Adobe Lightroom, each a minor update but also each comprising hundreds of megabytes!
To check if you've left giant downloads scattered about that you no longer need, the folks at the Omni Group offer a free utility called OmniDiskSweeper. It's not a de-duplicator, like the software above. Rather, it can examine a drive and list files from the largest to smallest, making it easy to see giant lumps you no longer need.
Ask Mac 911
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