Do i have to download any app to scan barcode on my note 4 ?

[kirrak]

And how do i use barcode scanner and what is nfc and what its for ? Plz can someone help me with this ?

 

[Rukbat]

Depending on the carrier, you may already have a barcode scanner. If not, there are plenty of free ones in the Play Store.

NFC is Near Field Communications - like the new credit cards you just pass ofer the scanner without having to swipe them (different technology, but the same kind of usage). You can transfer data from one phone to another with NFC - but it's so slow that unless it's a phone number you're better off texting the data. (The limit on texting is 1MB, but sending 1MB on NFC isn't something you want to stay awake for.)