Remote Controller Apps and Alternatives

When using the appropriate app, a Mac can be accessed and controlled from another computer, in other words, a user is capable to remotely operate a the Mac.

To be able to establish a remote connection, users simply need to specify the IP address of the target Mac.
 
However, there are some remote controlling apps that require a client application to be installed on the target Mac in order for the connection to work.

Once remotely connected, one can monitor the other computer's activity, launch or install programs, or even turn it off it is needed.