« Gang » is a term that implies several meanings. The «formal» definition for a gang refers to an organized group of criminals. But is also alludes to a group of young people with a disorderly conduct. More routinely, a gang is a crew of buddies meeting and doing things together.
In other words, all these definitions are miles away from the very first meaning of the word. In the past, a gang used to designate a group of manual workers.

The word has many synonymous, and when we speak of a gang as a criminal organization, we may also speak of a mob. Mobsters, or gangsters are the members of a criminal gang. In the early 20th century, the criminal gangs patterned their methods after the Italian Mafia's way of proceeding. A member's traits of personality and singularity had to disappear for the group as a single entity, (strong, united, with a unique identity) to emerge. Sharing the gang's identity was often expressed through displaying many tattoos (the Yakuza for instance).

Within the most famous, and feared, gangs from history, it's worth mentioning the Muslim Hashshashins or assassins: from a historical view point, an assassin is defined as “a member of the historical Ismaili Muslim militant group”. This group, or gang to stick to the word, was known for assassinating in public its enemies. According to the myth, the leader of the gang would distribute hashish his disciples, for them to be more easy to command. The word “hashish”, for cannabis, gave birth to “Hashshashins” and then to assassins, for murderers.

Nowadays, the term is used in a quite pejorative way. Referring to a group of young people as a gang implies that you have many prejudices against the youth. A gang, for many people, comes from the “ghetto” or “hood”. People think they know what they're talking about when they speak of a gang. They picture young people from these so-called gangs with a ghetto-blaster put on their shoulder, a gun slipped on their waistband, a cap topping their skull, and an inability to speak otherwise than with rapping and rhyming words. To be true to them, some young people refer to their band of buddies as a gang to highlight their opposition to the mainstream norms. They share many similarities with the older “gangs” from the 20's: the statement of identity and the fact that the average man doesn't trust them.