There is so much good information on Apple's various tech support and warranty websites that it can sometimes be a challenge to find information for your specific model laptop/desktop. Here's a quick tip to help you find that information... quickly.
If you click on the Apple logo in the top left-hand corner, you will see an option called "About This Mac...". Upon opening this, you will see a very small subset of information related to your Mac.
From here, click on "More Info..." at the bottom of the window. This will open a new window with a little more information related to your Mac, as seen here:
As you click on the various tabs along the top of the window, you will see some good information related to your system (hardware and software). Probably the most useful areas of this screen are the "Support" and "Service" tabs on the right side. Clicking these tabs will give you links to Apple websites that offer detailed information regarding that specific computer (including support, service information, detailed specifications, etc).