Terminal is one handy app, I’ve got to say. There are a ton of amazing things you can do with it, as it’s essentially the back end control room of your Mac. All the Unixy underpinnings of your operating system can be accessed in here, and while it’s possible to completely hose your system with the wrong command (rm * comes to mind, for one), there are a lot of helpful things you can do with it as well.
RAM is the type of memory your Mac uses to run active applications in, as opposed to the kind of memory on your hard disc or SSD drive. The more memory you have, the faster memory-dependent apps (like Photoshop or Final Cut Pro, for example) will seem to run, and the more everyday apps you can run at once. While old-school Mac users will remember needing to close all the applications to free up memory, that’s really not as necessary as it used to be with the advanced memory handling routines in Mac OS X. However, on occasion, you might want to try the purge command in the Terminal.
Purge frees up the RAM on your Mac, telling each running app to release all the RAM it was given at launch that it is not currently using. It’s like a mini reboot without the stress.
Launch Terminal from the Utilities folder in the Applications folder. Once launched, type
then hit Return on your keyboard and your Mac will force all your running apps to release the RAM they don’t need. This means you have more free RAM to run more apps, or to let heavy RAM using apps grab a bit more, running just a bit faster. You Mac may take a second or three to complete the purge task, but don’t worry – this is safe, and won’t bork your machine.
- Source LifeHack