Altissimo notes have unlimited high ranges that can only be reached by skilled players with developed lips. Most fingering charts have the first few altissimo fingering

Unskilled or entry level.

When non-skilled and semi-skilled pay exceeds the pay of skilled workers, the skilled workers can form a union to battle for higher pay. This is actually how unions were formed originally.

Skilled workers have better success with organizing than non-skilled because the skilled workers are harder to replace.

Scribes were skilled in writing.