Causar vs. ocasionar vs. provocar

The Spanish verbs 'causar', 'ocasionar', and 'provocar' all translate as 'to cause' in English. Although they bear similar meanings, they're used slightly differently depending on the context.

Causar

This is the general term for 'to cause'. It is versatile and can be used with a wide range of objects or circumstances.
El alcohol puede causar daño al hígado.
(Alcohol can cause liver damage.)
Su negligencia causó un gran accidente.
(His negligence caused a big accident.)

Ocasionar

Though also translating to 'to cause', this verb often carries a connotation of an indirect, less immediate cause. It's typically used to refer to consequences resulting due to an action, behavior, or circumstance.
El mal tiempo ha ocasionado retrasos en los vuelos.
(The bad weather has caused delays in flights.)
La falta de comunicación puede ocasionar malentendidos.
(Lack of communication can lead to misunderstandings.)

Provocar

'Provocar' usually indicates an intentionality or deliberate action taken to generate a certain outcome or response. It also implies a stronger degree of causality than 'ocasionar'.
Sus comentarios provocaron risas en la sala.
(His comments provoked laughter in the room.)
La nueva ley ha provocado protestas en toda la ciudad.
(The new law has provoked protests throughout the city.)

Summary

While 'causar', 'ocasionar', and 'provocar' all mean 'to cause', each word carries slightly different nuances. 'Causar' is the most general term; 'ocasionar' generally refers to indirect, consequential causes; and 'provocar' implies intentional or strong causal actions.