In its simplest form, a GOAL is a dream with a DEADLINE. Without a deadline, a dream remains a dream. And while it is nice to dream, it is so much nicer to realize that dream.
I was also taught that a goal must be S.M.A.R.T. :
Specific - color? brand? model? location?
Measureable - how much? how big? how high?
Attainable - can it be done within the timeframe?
Realistic - don't expect to swim across the English Channel if you can't even swim at all.
Time-bounded - when? how soon?
To this I would like to add P for Personal - a goal must be something that I can adopt as my own. A goal must be something that will bring me personal satisfaction when achieved or personal pain when I fail.
Goals may be classified into several categories:
Goals I set for myself,
Goals my boss sets for me,
Short-term goals - monthly and annual targets
Long-term goals - 5-year plans, 10-year plans, retirement plans