Often within cultures, a sense of stagnation can develop, where the expectations by elders of the conformity of its young defies the instincts and desires of young people. The attitude of non-conformity with the establishent is usually characterised by said establishment to be disrespectful, thoughtless, or inconsiderate.
The difference between rebel and terrorist is subjective. While the term rebel can sometimes have positive connotations as an agent of change, "terrorist" implies destructive action and is always used pejoratively, often by an establishment opposed to rebellious activities.
Rebel groups in reality