Helium Network Overview and Basics
LoRaWAN Networks Versus the Helium Network
LoRaWAN Network Gateways Versus Helium Hotspots
Helium Hotspots are a specialized implementation of LoRaWAN network gateways. Helium Hotspot manufacturers must be approved by the Helium Foundation. The full list of requirements can be found here, and the list of Helium-compatible Hotspots here.
In addition, do-it-yourself data only Helium Hotspots can be used to extend network coverage, but are not able to earn proof of coverage or data transfer HNT rewards.