Traditional and Managed Care.
Within those categories, there are four basic types of plans:

Traditional indemnity plans, which are now often called fee-for-service plans;  PPO, or Preferred Provider Organizations;  POS, or Point-Of-Service plans;  and HMOs, or Health Maintenance Organizations.  No one type of health care plan is better than the other. It really depends on your needs and preferences. Some people enjoy the autonomy offered by fee-for-service plans, while others prefer the low costs associated with closed-panel HMOs. Also, as health insurers compete for business, distinctions among the types of plans may blur. (For a quick description of the different types of plans, click below.) 

"Traditional" Health Insurance

Fee-for-Service

Managed Care

Preferred Provider Organizations (PPOs)

Point-of-Service (POS)

Health Maintenance Organizations (HMOs)