The landlord generally buys insurance coverage to protect their interest, such as the building, loss of rents, liability, etc. It does not cover your property.
What renter insurance usually includes
Renter insurance normally combines coverage for:
Personal liability
Protects you from claims other people make against you.
Premises medical coverage
Pays the medical costs of others accidentally injured at the place you rent.
Additional living expense
Pays for your living costs if you can't live in the place you rent and have to stay somewhere else temporarily.
Personal property (contents) coverage
Renter insurance usually only covers your property's actual cash value at the time it was damaged or destroyed. For some personal property, like gold or jewelry, your insurance will cover a specific amount of money.
Your insurance may pay less than what your property is worth, so you may want to buy more coverage.
What renter insurance doesn't cover
It doesn't cover the building you're renting but may cover improvements you add, such as built-in bookshelves or room dividers.