The Computer Folder in OS X Yosemite
The Computer folder is the top level of the folder hierarchy in OS X Yosemite. The Computer folder shows all the storage devices (hard drives, CD- or DVD-ROM, USB flash drive, and so forth) that are connected to your Mac. The following steps show how you can start at the Computer folder and drill down through the folder structure:
Choose Go→Computer or press Shift+Command+C.
Now you are at the Computer folder. Here, the Computer folder is called Doctor Yosemite (look in the title bar), and it contains a solid-state drive icon (Yosemite SSD) and a Network icon, from which you can access servers or other computers on your local network.
You might have more or fewer icons in your Computer folder than you see here, depending on how many disks you have mounted.
You might also find a Computer icon in your Sidebar. If not, choose Finder→Preferences, click the Sidebar tab at the top, and then select the check box for your computer.
You can change a Mac’s name (Doctor Yosemite) by opening the Sharing System Preferences pane and changing the computer’s name in the Computer Name field.
Double-click the icon that holds your OS X stuff.
Technically, this drive is called your boot drive. In the figure, that hard drive is called Yosemite SSD. I have no idea what yours is called, of course; if you haven’t changed it, it’s probably called Macintosh HD.
Check out the folders you find there.
You should see at least four folders, unless you’ve added some. (If you installed the Xcode programming tools, for example, you have more.)