What is the difference between the verbs 'essere' and 'stare'?

Both of the Italian verbs 'stare' and 'essere' can be translated into English as 'to be' in certain contexts.

'Essere' means 'to be' or 'to exist' whilst 'stare' usually means 'to stay.' 'Essere' is most commonly used, such as to give details concerning profession, nationality, religious/political affiliations, origin, identity etc.

For example: Sono inglese = I'm English.

'Essere' is also used to give the date/time.

For example: Sono le dieci = It's ten o'clock.

Finally, 'essere' is used to describe something/someone and to give personal observations or reactions.

For example:

Gli uccelli sono neri = The birds are black

Sono felice = I'm happy

L'atmosphera è strana = The atmosphere is strange.

 In certain idiomatic expressions, 'to be' is rendered with 'stare' rather than 'essere' in Italian.

For Example: sto bene/sto male = I'm well/I'm unwell.

'Stare' is also used to give the precise location of objects or sometimes people.

For example: Il divano sta nel salotto = The sofa is in the living room.

N.B. 'Essere' can also be used in this context, for example- Il divano è nel salotto = The sofa is in the living room.

The final use of 'stare' to mean 'to be' is to form the Continuous Present Tense, which is used to express an action taking place at a specific moment in the present. It is formed by conjugating 'stare' in the Present Tense plus the gerund form of the action verb.

For example: Sto mangiando una pizza = I'm eating a pizza.