"NFC (near field communication) is a wireless technology which allows for the transfer of data such as text or numbers between two NFC enabled devices. NFC tags, for example stickers or wristbands, contain small microchips with little aerials which can store a small amount of information for transfer to another NFC device, such as a mobile phone.
What information can you store ?
There's a whole set of different data types you can store on an NFC tag. The actual amount of data varies depending on the type of NFC tag used - different tags have different memory capacities. For example, you may choose to store a URL (web address) or a telephone number. A standard Ultralight nfc tag can store a URL of around 41 characters, whereas the newer NTAG203 nfc tag can store a URL of around 132 characters."
"NFC tags can be small stickers, which contain a small unpowered NFC chip. Depending on how the tag is programmed, it can change various settings, launch apps and perform certain actions just by holding your phone close to it. To do this, the tag takes a small amount of power from the smartphone and sends its stored information onto it."
"This process uses Near Field Communication (NFC), a feature we've talked about once before. You've probably even seen it in commercials, where people share playlists and perform other actions just by touching their phones together. Those uses haven't really caught on, but NFC tags will work anywhere-they're basically tiny stickers, keychains, and other trinkets that perform tasks when you tap them with your phone."