vs
QUICK ANSWER
"Si" is a form of "si", a conjunction which is often translated as "if". "OK" is an interjection which is often translated as "OK". Learn more about the difference between "si" and "OK" below.
si()
A conjunction is a word that connects words, phrases, clauses, or sentences (e.g., The cat and the dog slept.).
A masculine noun is used with masculine articles and adjectives (e.g., el hombre guapo, el sol amarillo).
OK()
An interjection is a short utterance that expresses emotion, hesitation, or protest (e.g., Wow!).
