There are several types of travel insurance, depending on whether you travel alone or in a group, whether you want to be covered for a single trip of for whole year and what do you want to have included.
Travel insurance packages vary among various insurance agencies (and travel companies that sometimes also offer some kind of travel insurance policy) and cautious comparison of conditions is vital.

Risks typically covered by travel insurance include:
-Delayed departure
-Cancellation
-Delayed baggage
-Legal assistance
-Medical expenses (either emergency only or enhanced)
-Accidental death and funeral expenses (flight insurance is a special product covering death during flight)
-Repatriation/evacuation
-Some car rental insurance products, usually covering deductible or theft of personal items from the rented vehicle

The single most important issue to check with your insurance company is your medical insurance, namely what is and what isn't included and what is your coverage. We strongly advise you to buy high medical coverage and include as many possible health complications as possible, not just the basic emergency insurance.
Liability insurance for car rental is sometimes included but it almost always goes with the car rental anyway (except for USA).
Dangerous activities like paragliding, windsurfing, winter sports or scuba diving are not covered under normal circumstances but may be added for a (rather high) special fee.