I don't understand 'ser' and 'estar' althought I look through the description like a 10000 times?
What is it actually ?
This is one of the most confusing things to beginning learners. The most basic way to explain it is that they both mean "to be". But "ser" means "to be permanently", while "estar" means "to be temporarily".
Yo soy de los Estados Unidos - I am from the United States. Can't change. I was born there.
Yo estoy en España - I am in Spain. Could change as soon as I fly to another country.
If you're talking about something being someplace you usually use estar. Same thing with sick, well, happy, sad, etc. If you're talking about a permanent feature of something, it's usually ser - tall, short, red, blue, heavy, light, etc.
And then there are all the exceptions. But permanent vs. temporary is a good start.
Echoline posted a great answer to that on another thread:
At the core of it all, the easiest way to remember the difference of when to use ser and estar is philosophical. It is unfortunate that we don't have this concept in English, as it is a beautiful and useful difference. Ser is used when you are describing the immutable part of you, the intransitory. Estar is for the things in life that come and go, like your location. Ser is your essence....estar comes and goes.
Her complete answer to that is at link text
The most basic way to explain it is that they both mean "to be". But "ser" means "to be permanently", while "estar" means "to be temporarily".
Be careful with that permanent / temporary "rule!!!"
You won't always be a student, but it's "Soy estudiante."
He will always be dead, but it's "Está muerto."
New York will always be located in the U.S., but it's "NY está en los Estados Unidos."
If you go to the answers tab at the top of the page, then look under where it says "New, Hot, Categories," etc. Find the search box and type in "ser estar" (just those two words) and you will find tons of questions similar to yours that already have very good answers! Maybe those will help you understand more clearly.
ser is a Spanish verb infinitive meaning to be
and guess what
estar is a Spanish verb infinitive meaning to be**