You can access a computer inside a LAN using its IP address. If you don't want to remember addresses like
192.168.60.105 or similar, you can set a hostname for it.
The Host IP address is the IP of the client who should get a name. The Hostname is the clients new name.
The Domain name can be left as-is or can be empty. Enabling Generate PTR will create a DNS pointer record (a PTR) and is used in reverse DNS lookups. The Hostname will be activated if Enabled is checked.
Click on Add to save the settings.
If you have set up the hostnames correctly, it should look similar to this screenshot.