NOOBS is a system designed by the Raspberry Pi foundation for installing operating systems onto your Raspberry Pi's SD card. Not only are you able to install an operating system with a single click, but you can install it over a network or even install multiple operating systems on multiple partitions.
For example, if you ever wished you could install both Raspbian and OpenELEC, NOOBS not only makes this possible, but easy to switch back and forth between the two.
NOOBS requires a couple of things, most of which you probably already have:
One thing you must take note of is the 4 GB SD card requirement. If you have a smaller SD card or you simply need a new one, there are several cheap models that you can purchase:
All of the above micro SD cards come with adapters, so if you want to purchase the micro SD you can use it in your original Raspberry Pi and later move it to a model A+/B+ or newer at a later time.
You can also purchase an SD/micro SD card with NOOBS preinstalled. This is more expensive than just loading NOOBS onto an SD card yourself, but is an option for convenience:
First, you must download the NOOBS image from the Raspberry Pi website. There are a couple different options for download:
The offline installer is significantly larger than the "LITE" version, but comes with the ability to reinstall the Raspbian operating system without a network connection. This is because the actual OS image is saved onto the SD card when you install NOOBS for the first time. However, over time the OS image that is included in the NOOBS installation may become outdated unless you have a network connection, in which case the newer OS version will be downloaded and installed.
NOOBS LITE is significantly smaller in size, but requires a network connection to install the OS images. Both the regular NOOBS and NOOBS LITE installers allow for installing from a network.
Once you've downloaded the version of NOOBS you prefer (either the regular version or LITE), then you can simply extract the ZIP file.
Before you can actually place NOOBS onto your SD card, you must format it. Note, formatting the card erases all data on it1.
On the Mac, you can use the built in "Disk Utility" application. Launch "Disk Utility" and insert your SD card into your Mac. You'll see it in the sidebar of the application, along with some items that are indented underneath it (what these items are and the number of them will vary based on how you previously used your SD card).
Ensure you select the root SD card (that is, the top most item), and switch to the "Erase" tab on the right hand pane. Leave the format as "FAT" and choose a name for it, which will be all uppercase letters. Then, simply hit the "Erase..." button in the bottom right to format the card.
Because we want to format the entire card and not just a single partition, you may want to use the SD Card Formatter by the SD Association. Once you've downloaded the formatter from their website, insert your SD card and run the formatter tool.
When you open the formatter tool, you'll have a few options-- the SD device to format, the type of format operation, and the new name of the SD card. Make sure you select the right SD card if you have multiple SD cards plugged into your computer. You can choose either format type, though the quick format is usually sufficient if you are not trying to erase sensitive data. Finally, for the name, choose whatever you wish and fit the "format" button.
Once you have a formatted FAT SD card, you can simply copy the files for NOOBS that you extracted earlier. A simple copy and paste is all that is needed. It might take a while to copy the regular version of NOOBS due to the slow speed of SD cards, but once it's done you can eject the card from your computer and insert it into your Raspberry Pi.
Before you plug your Raspberry Pi into the power cable, attach a USB keyboard and mouse so that you can navigate the NOOBS interface. Once you have the keyboard and mouse plugged in, you can turn on the power to your Raspberry Pi and you should be greeted with a screen similar to the following:
This is the operating system installation screen, and allows you to choose one or more OS images to install onto your SD card. Notice the icons on the right hand side-- those OS images with a picture of an SD card are already included with your NOOBS installation, while those with an Ethernet symbol can be downloaded over a network.
Simply check the boxes next to the OS images you wish to install, and hit the install button in the toolbar at the top of the window.
Once you've installed one or more operating systems with NOOBS, rebooting your Raspberry Pi will result in one of two things happening automatically:
To get back to the OS installation screen, simply hold the "shift" key on your keyboard as you turn on your Raspberry Pi.
If you wish to just install a single operating system, you might find my tutorial on installing the Raspbian OS directly onto your SD card. With this method, the Raspberry Pi will automatically boot into Raspbian, though you do not get any sort of interface for reinstalling the operating system.
Advanced information on the NOOBS system can be found in the GitHub repository. This includes info on silent installation, as well as configuring advanced parameters such as choosing your auto-boot partition or forcing a display mode.