Error vs. fallo vs. equivocación

While the Spanish words 'error', 'fallo', and 'equivocación' all translate to 'mistake' or 'error' in English, they are used in distinct contexts. Each of these terms is geared towards a particular type of mistake or error, and their use often depicts the nature and gravity of the mistake.

Error

An 'error' is a general term referring to any type of mistake or incorrect action. It is usually used when pointing out inaccuracies or missteps in formal situations like science, law, and mathematics.
Hiciste un error en la ecuación matemática.
(You made an error in the mathematical equation.)
El juez cometió un error de derecho.
(The judge committed an error of law.)
Los científicos se dieron cuenta del error en su experimento.
(The scientists realized their mistake in the experiment.)

Fallo

'Fallo' often refers to mechanical malfunctions or failures. It can also be used to describe a lapse or shortcoming in human performance or judgement.
El fallo del motor provocó el accidente de coche.
(The engine failure caused the car accident.)
Había un fallo en el sistema de seguridad.
(There was a failure in the security system.)
El fallo en su razonamiento le costó la partida de ajedrez.
(His lapse in judgment cost him the chess game.)

Equivocación

'Equivocación' refers to a misunderstanding, misconception, or false belief that leads to a mistake. It's often used to communicate misunderstanding or confusion resulting from misinformation.
Hubo una equivocación acerca de la fecha de la reunión.
(There was a misunderstanding about the date of the meeting.)
Tuve una equivocación en las instrucciones que recibí.
(I had a misunderstanding about the instructions I received.)
La historia estaba llena de equivocaciones y errores factuales.
(The story was full of misconceptions and factual errors.)

Summary

To summarize, although 'error', 'fallo', and 'equivocación' all describe different forms of mistakes, they are best used in specific contexts. 'Error' for formal technical mistakes, 'fallo' for mechanical failures or performance lapses, and 'equivocación' when there is a misunderstanding or false belief involved.