What is the difference between the verbs "ser" and "estar"?

The verbs "ser" and "estar" both mean "to be", but the difference between them is the permanence of what you're describing. "Ser" is used to describe things that are permanent and always will be true - such as the country you were born in. If you were born in England, this is a permanent thing which will never change (you will never not be born in England), and thereby you say "soy de Inglaterra". "Estar", on the other hand, is used for temporary occurrences. Such as saying you are currently in your house - "estoy en casa" - this is a temporary occurrence and thereby "estar" is used.