Hiden (秘伝, Secret) Jutsu are passed down from generation to generation in certain regions or clans.
The groups possessing these techniques are usually extremely secretive about them, ensuring no-one other than the members of the group learn them. Only a scarce few Hiden jutsu require a special ability or lineage, but they are simply not taught to those outside the group. These jutsu are usually the pride and fame of the clan that possesses them.
They are not to be confused with Kekkei genkai, jutsu that require a specific genetic ability.