A mortgage is a term used to describe a loan taken out to buy a property or land.
You take out a mortgage from a mortgage lender to buy a property, and you make monthly payments to repay the amount, while you live in that property.
The mortgage lender has the option of taking the property and selling it if the mortgage repayments aren’t made. This is so that the lender doesn’t lose money as they would be making it back from the property sale.
Any time you take out a mortgage, the loan is then split into two aspects. One of which is the interest, which is what the lender charges for lending the money. The other is the capital, which is the actual amount of money used to purchase the property.