Medicare supplemental insurance is a popular policy among seniors who want more protection than Medicare alone can provide. It's a smart purchase for the price, but it's essential you go into it knowing what you want, and what you need.

Medicare is the basic health plan Americans over 65 rely on for the bulk of their health care needs. However, this care is limited, and Medicare supplemental insurance is a means of extending coverage and reducing out-of-pocket expenses.

There are three different types of Medicare policies to choose from:

• Medicare Traditional
• Medicare Advantage, formerly Medicare Plus Choice
• Medicare Select

All plans vary by where you receive services.