What it means
A Remote Desktop host accepts incoming control sessions for its desktop. A client initiates a connection to another machine. Windows Home can act as a client but cannot host built-in Remote Desktop sessions, while supported Pro and other editions can host them.
A real-world example
A person turns off Remote Desktop on a home laptop because they never allow others into it. They can still use an approved client to reach a work PC, subject to that work PC's own access rules.
What to do
Disable host access where unused. If hosting is necessary, review allowed users, network reachability and Network Level Authentication with the device owner.
The distinction that matters
The Windows host toggle does not manage unrelated remote-support applications. Microsoft describes incoming Remote Desktop as access to apps, files and network resources, so leaving it on without purpose adds avoidable exposure.
Microsoft's Remote Desktop documentation
