When this setting is enabled, Windows 8 and 8.1 are capable of detecting and setting up automatically network devices like hard drives attached to your router or other network devices. This devices can then be used by Windows 8/8.1 to provide you with services like automatic backups through the File History service. More details about how this works can be found in this guide: What is the Automatic Setup of Network Connected Devices in Windows 8?
If you don't have hard disks attached to network devices or PCs or you have them but you don't need to use them over the network, turning off this setting is OK. Otherwise, you should keep it enabled so that you can use these devices over the network.