In previous versions of Mac OS X, Apple introduced Spaces as a way to have multiple "desktops" or workspaces on your Mac. This has now been integrated with Mission Control in 10.8 (Mountain Lion). Mission Control has other features, but today I want to discuss Spaces because I think it's a very useful feature, if you need it.
Spaces is, in one way, a kind of a workaround for not having dual monitors. If you only have one monitor but need more desktop real estate (more space for all those windows!), Spaces is one way to solve this. While not quite the same as having two monitors, it certainly can make life easier.
The way it works is by allowing you to create two or more "virtual desktops" which you can switch between whenever you want using mouse gestures or keyboard shortcuts. So, for example, let's say I have two spaces. We'll call them Space 1 and Space 2 for want of a more useful description! In Space 1, I can have maybe my browser window, Skype and Mail windows open. Then, with a quick key stroke of the hotkeys (which are configurable to your taste), I can quickly switch to Space 2 with a nice sliding animation effect where one screen slides off to the side revealing my new workspace (Space 2). In Space 2, I decide to put some of my development windows, such as SublimeText and SQL browser, CodeKit and MAMP. I need access to all these windows while coding and I like them all laid out to my own working style. What I don't need is to have to move all those windows around when I want to see my Mail or Skype windows.
That's the real power of Spaces. So with a single keystroke combination I can quickly switch from one workspace to another, as if I was actually switching from one physical monitor to another. Everything stays neatly arranged on screen in each Space and it makes my working day that bit more pleasurable. Granted, many people may not have the need to use Mission Control for multiple workspaces, but for those that do it's a real life saver!
One thing to note though is this. Even though you can kind of use this as a substitute for not having dual monitors, if you do have dual monitors, it gets even better. If you're using dual monitors in extended desktop mode, when you use Spaces you actually get both monitors in both Spaces. Now we're talking maximum screen real estate!
I can see that Spaces probably has many different potential applications. Has anyone else got any great examples of where they use Spaces in a slightly different way?