Thread is a mesh protocol on 6LoWPAN, which in turn is based on the same underlying 802.11.4 as Zigbee in the 2.4 Ghz spectrum.
Its claims to fame is having reasonable response times/batteru life and being based on IPv6. Being based on IP allows devices to talk to one another, and for bridging those devices to the broader network and potentially to the internet with clear layer separation.
Matter is a IP-based IoT discovery and use standard. Devices advertise Thread and/or Wifi support for wireless support. It also standardizes onboarding (I know BLE is an option there) and the underlying security, and mandates certain capabilities such as supporting multiple 'admin' software at once.
Devices using other wireless tech can also theoretically work with Matter with a gateway that does protocol translation, supports device onboarding, and then exposes them onto the network.
Thread is a mesh IPv6 based network that operates over the 2.4 GHz ISM band but is not WiFi. Matter is a communication protocol built on top of Thread, WiFi, and BLE (and potentially others in the future).
Thread and ZigBee operate in the 2.4 Ghz and also 833/915 Mhz although in practice I've never seen any devices that explicitly claim to be using the sub Ghz bands. It's not WiFi, it's IEEE 802.15.4. Matter supports devices connected through WiFi, Thread and Ethernet with BT provisioning.
Its claims to fame is having reasonable response times/batteru life and being based on IPv6. Being based on IP allows devices to talk to one another, and for bridging those devices to the broader network and potentially to the internet with clear layer separation.
Matter is a IP-based IoT discovery and use standard. Devices advertise Thread and/or Wifi support for wireless support. It also standardizes onboarding (I know BLE is an option there) and the underlying security, and mandates certain capabilities such as supporting multiple 'admin' software at once.
Devices using other wireless tech can also theoretically work with Matter with a gateway that does protocol translation, supports device onboarding, and then exposes them onto the network.