Simply put, real estate is a term used to identify any and all pieces of land along with all permanent objects having space on that land. Permanent objects include buildings, landscaping, fences, residental dwellings, underground structures, radio towers, roads, lakes, mountains, etc. -- basically any thing on the land, made by humans or occurring naturally that is deemed to be permanent.
Profits in real estate can be made a number of ways, the most common of which are either selling or renting property.
Another common way profit is made from real estate, especially by banks, is to issue mortgage loans to qualified buyers. There are many types of mortgage loans offered at fixed and variable interest rates. Typically, mortgage loans once agreed upon by each party involved are in effect for 30 to 40 years, or until the loan with all accrued interest is paid in full.
Relevent NAICS codes for real estate are: