What is the difference between Ser and Estar?

Ser and Estar are two verbs in spanish which both mean 'to be', but they have very different uses and therefore, are not interchangeable.Ser = permanent i.e. used to express an inherent quality or characteristic.Examples:(Yo) soy Escocesa = I am Scottish.(Nosotros) somos del Reino Unido.Este libro es de Juan.La casa es moderna.Sofia es muy amable.Estar = temporary i.e. used to express a temporary state or condition. Note: Estar is always used to describe location, even when the location is permanent.Examples:Carlos está ahora en Nueva York.Madrid está en España.El agua está fria.Hoy ella está feliz.