disk-spacemacos
Where do I have to go to find out how much space I have left on my hard drive?
As you can imagine from the question I am new to Apple and don't know where to look.
I used a program called "Cleanup" on my old Windows machine which did what the name says, great little program, is there anything similar for Apple, something which cleans up files like cache and cookies?
I suggest you download a utility that shows the size and arrangement of your files. Personally, I use DaisyDisk. It is shareware, so for your purposes, it would suffice to trial the software.
Mail attachments are stored in ~/Library/Mail Downloads/
It is unlikely that OS X is keeping packages after installation through Software Update. You should first look to your cache ~/Library/Caches/ and perhaps your sleepimage, which is located under /var/vm/sleepimage (note that the sleepimage is recreated every time the system goes to sleep. Read more about disabling it here if you are concerned with HD space).
DaisyDisk (or equivalent) will do a much better job at identifying where the "growth" has occured on your filesystem so that you may excise it than we ever could. I suggest you give it a try.
Disk Inventory X or WhatSize are both excellent apps for giving you a complete list of what's taking up space. Also, as you described there is a way to start at the root and check the size of each folder, drilling down until you find the culprit. Command-I or Get-Info from the the right click menu will show you the size of any folder or file you select.
Best Answer
Menu > About this Mac
Then the Storage tab
For cleanup, CCleaner exists for Mac; there's also CleanMyDrive & a whole raft of others. I wouldn't particularly recommend any of them, as they've all been known to throw out the wrong bit, just like on Windows.