What is an annuity? Is an annuity worth more or less than a lump sum payment received

Question:

What is an Is an worth more or less than a lump sum payment received now that would be equal to the sum of all the future payments?
Annuity
An annuity is a series of equal payment made at equal intervals during a period of time. In other words annuity is a contract between insurer and insurance company in which insurer make a lump-sum payment or a series of payment and, in return,...