1. Concepts & Origins

• RFID (Radio Frequency Identification): A wireless tech for identifying targets and reading/writing data (no mechanical/optical contact). Originated from military radar, commercialized in the 1980s. Similar to barcode scanning but uses radio signals; advantages include fast scanning, small/diverse tags, reusability, barrier-free reading, large storage, and encryption.
• NFC (Near Field Communication): A short-range branch of RFID (13.56MHz). Co-developed by Philips (now NXP), Nokia, Sony in 2003; managed by NFC Forum (members: Apple, Huawei, etc.).

2. Frequency Ranges

• RFID: Wide range – 125/133KHZ (low), 13.56MHZ (high), 900MHZ (ultra-high, varies by country: e.g., China 920.5-924.5MHZ, US 902-928M), 433MHZ, 2.4G/5.8GMHZ.
• NFC: Only 13.56MHZ (note: this frequency involves multiple protocols, so it’s not equivalent to NFC).

• RFID: Varies by frequency – a few cm to tens of meters.
• NFC: ≤20cm (uses signal attenuation for security; features short range, high bandwidth, low energy).

4. Communication Technologies

• RFID: Needs 3 parts (tag, antenna, reader); unidirectional (reader reads tag).
• NFC: Integrates reader, contactless card, P2P into one chip (bidirectional interaction). 3 modes:

Card Emulation: For payment/access (electronic ID).

P2P: Data exchange (e.g., music/pictures).

Reader: Reads info from tags (e.g., posters).

5. ConclusionSimilarities: 

• Physical layer overlap.
• Differences: RFID = unidirectional tag identification; 
• NFC = bidirectional short-range communication.NFC Payment: Slow development due to long industrial chains, but Google’s HCE tech (supported by UnionPay) brings prospects.