TAM is an abbreviation for Total Addressable Market, which is the total market demand for a product or service. It is calculated by multiplying the average cost of your product or service and multiplying by the total amount of people in your total market.
Serviceable Addressable Market (SAM) is a subset of your Total Addressable Market (TAM) that you can reach within a specific geographical area. It is a calculation of the total revenue you could earn by selling your product or service to everyone in that geographical area. SAM assists you in determining your potential revenue in a specific market and is useful in business strategy planning.
The Service Obtainable Market (SOM) is the subset of your Serviceable Addressable Market (SAM) that represents the portion of your potential market on a company, product, or service-specific basis that can be realistically obtained in a specific geographic area.