What is NFC?
NFC stands for Near Field Communication. As its name suggest, it enables short distance wireless communication technology between compatible devices.
This requires at least two devices to communicate, one device for transmitting, and another to receive the signal.
So, when two Near Field Communication-enabled devices are very close to each other, roughly around 4 to 10 cm, then they can communicate with each other using the radio waves.

Now, out of the two devices, at least one device has to be an active device like a smartphone, tablet or payment terminal.
While the other device active or passive and the example of a passive device is the NFC tag.
The active device means the device requires the external power supply while the passive device doesn’t require any external power supply and it is powered by the Electromagnetic field of the active device.
How does NFC works?
These NFC enabled devices to communicate with each other using the radio waves and these radio waves are generated using the antenna.
So, if you take the case of a smartphone, then the antenna is fitted on the battery or sometimes it is fitted on the back side of the back cover.
While in the case of the NFC tag, if you tear down the tag, you will find the antenna pattern. So, using these antennas, devices are able to communicate with each other.
Modes of Near Field Communication
To determine what sort of information will be exchanged between devices, the NFC standard currently has three distinct modes of operation.
- Peer-to-Peer Mode
- Rear or Write Mode
- Card Emulation Mode
The most common mode used in smartphones is the peer-to-peer mode.
This allows two Near Field Communication-enabled devices to exchange various pieces of information between each other. In this mode, both devices switch between active when sending data and passive when receiving.
Read or write mode is one-way data transmission. The active device, possibly your smartphone, links up with another device in order to read information from it. NFC advert tags use this mode.
The final mode of operation is card emulation. The NFC device can function as a smart or contact less credit card and make payments or tap into public transport systems
Standards of NFC
Some standards are defined in Near Field Communication to establish communication between the two devices.
So, these standards are derived from the already existing standards which are used for radio communication. These standards are NFC-A,-B,-F, and -V.