You have just experienced your first practical exercise in
general semantics. As you will hopefully come to understand, all
of these are partially correct, and all of these are necessarily incomplete.
One of the things that the study of general semantics teaches us is that
there is always more to know, always more to be said. (More on this later.)
However, a relatively simple (and as you will come to see, grossly
incomplete) answer to the original question follows:
General semantics is a system of formulations, ideas, and practical
tools which help us to better understand and evaluate the world around
us by understanding how the words and ideas we use shape our perception
of and therefore our actions in and reactions to the world around us.
It encourages us to examine how we perceive things, how we label and categorize
them verbally, and how our word-maps then proceed to govern how we live
and experience. Further, it gives us tools for better understanding
and interacting with the rest of the world and hopefully living happier
and more fulfilling lives as a result.