To me, one of the most useful words for Spanish learners is the little word: hay and its past tense, hubo.
Why are these so useful? Hay means ” there is” / “there are” and hubo stands for “there was” / “there were”.
So, if you wake up in a Spanish speaking country and need a cup of coffee, all you have to say is … ¿Hay café? and hopefully, the answer will be .. Sí, hay café. (Yes, there is coffee).
For those who love grammar, HAY is the impersonal form of the verb HABER in the present indicative. It is a very old verb meaning:
to happen, to be necessary, to be, or to exist. For more information look here.
Some examples: Hay muchos barcos en el río – There are many boats in the river
Hubo un terremoto en Arequipa – There was an earthquake in Arequipa.