In Catalan, the word castell literally translates into castle, while in English its meaning is specifically that of a human tower.

Members of the pinya (most often men)[6] also act as a 'safety net' if the tower structure collapses, cushioning the fall of people from the upper levels.

It is not uncommon—when not in competitions—for other colles to assist in the pinya when a small colla is attempting a specially demanding structure in terms of people needed.

Then, when the signal to proceed is given, bands begin to play the traditional Toc de Castells music as a hush comes over spectators of the event.

Typically castellers wear white trousers, a black sash (faixa), and a shirt in their collaʼs color, with the team's emblem.

[8] Castellers also usually wear one or more bandanas (mocadors), usually red with white spots and the team's emblem, for various purposes including to hold the faixa in place, to provide an additional handhold, to tie back hair, or to protect the top of the head.

This tasselled piece of cloth varies in length and width and depends on the casteller's position inside the tower and also on choice.

Performing castellers always go barefoot when climbing, so as to avoid injuries, for greater sensitivity when balancing, and for better feel and grip.

[9][10] The motto of Castellers is "Força, equilibri, valor i seny" (Strength, balance, courage and common sense).

[11] This motto is taken from a verse of Els Xiquets de Valls by Josep Anselm Clavé, a Catalonian politician and composer.

[12] Accidents are rare during the construction of a castell; however, as in every other crowded cultural event, ambulances are stationed nearby in case a person needs immediate attention.

Terms denoting special construction techniques include: Another aspect of castell nomenclature refers to how successfully the tower was completed.