The Verb Estar
The verb Estar is used to indicate temporary states such as Yo estoy contento hoy (I am happy today) and locations like Tú estás en la escuela ahora (You are in the school now).
It is an irregular verb, so you need to study. This is how it reads:
Uses of the verb Estar
It is important to know that these temporary states and locations include things such as:
Ella está triste (mood)
Nosotros estamos enfernos (condition)
Madrid está en España (location)
The trickiest thing for an English speaker learning Spanish is to remember that the English language only uses one verb (TO BE) for both the verb SER and the verb ESTAR.
My top tip is to used SER when something is permanent and ESTAR when something is temporary (except in the case of locations, for which ESTAR is also used).
Ser or estar
Moreover, both the verbs ser and estar can be used with the same words, but the meaning is different. Here are some examples:
ser aburrido - estar aburrido
ser cansado - estar cansado
ser feliz – estar feliz
Let me teach you some real example in this video.