QR codes allow you to quickly and easily store and retrieve data within a single image. Much like barcodes at grocery stores, QR codes are images that can be scanned to discover data, such as an online website URL. Additionally, they can also be created by inputting text data into a QR code generator. Try scanning some of the QR codes in this video with an app on your phone or tablet to see how they work!
Oh... and if you're working from home these days, be sure to check out Gadget Hacks' Working-From-Home Essentials.