When people talk about a mortgage payment, they usually mean more than the loan itself. Lenders bundle several costs into one monthly bill. The core four are known as PITI.
Principal
The portion that pays down the money you actually borrowed. It starts small and grows every month as your balance falls.
Interest
The lender's charge for lending you the money. It starts large and shrinks over the life of the loan as the balance drops.
Taxes
Property taxes set by your local government, based on the assessed value of the home. Lenders usually collect these monthly into escrow.
Insurance
Homeowners insurance protects the property against damage. Like taxes, it is often escrowed and paid by the lender on your behalf.
PMI and HOA
If you put less than 20% down, private mortgage insurance is usually added until you build equity. If your home is in a managed community, HOA dues are a separate monthly cost that lenders do not collect but you still have to pay.