I recently learned that there are other wireless technologies besides Wi-Fi and Bluetooth. Can someone tell me what they are for? Which ones are used in IoT devices?
There are a lot of wireless technologies. Peer-to-Peer is when only two devices participate in a direct connection. A lot less known than WiFi is WiFi Direct which is P2P connection too. The Near-Field Communication, well known as NFC, is one of them. IoT devices usually use Bluetooth Low-Energy (BLE) (popular for sensor data), Zigbee (home and industrial automation), 6LoWPAN, Z-wave (when you need less other devices on this frequency). They all have their own characteristics and advantages. Local Area Network is a connection which several devices can be connected to. Except WiFi, popular are LTE, LTE-M, LoRa. All alternative wireless technologies are popular with IoT primarily because they require significantly less power then classic solutions like WiFi and Bluetooth. Smart devices usually don't need to transfer a lot of data.