Airlines sometimes offer special discounted airfares for people in particular groups or in special situations. Make sure you know whether you are entitled to one of these special fares before you book:

1. Students and Teachers. Many of the major airlines will offer a discounted rate for students who have an International Student Identity card (ISIC). This card can also save you on other travel expenses, such as lodging and travel insurance. It's easy to get a card: All you need is proof that you are at least 12 years old and a full-time student. The card does come with a small fee, but frequent student travelers will find that the card pays for itself rather quickly.

This same organization also provides discount travel cards for young people (under the age of 26) who are not full time students, as well as cards for full time teachers and professors. If any of these special situations apply to you, you can get more information on how to apply by visiting the ISIC website.

Beyond the ISIC, there are several companies that cater to student discount travel. If you are a full time student, conduct an online search for "discount airfare student" and see what's available for reduced fares before you book.

2. Military Discounts. Most airlines offer a military discount. But you may be able to save even more by shopping around. Also, keep in mind that typically these military discounts are reserved for the military ID card holders, and most often not for extended family.

3. Seniors. Many airlines (particular the discount airlines) will offer a senior discount, for as much as 10 percent of the airfare. Make sure to shop around before you book. You may be able to get a better deal on the flight without your senior discount.

4. Groups and memberships. You don't need to travel with an AAA or AARP group in order to get the discounts. If you belong to any of these groups, make sure to mention it at the ticket counter, as well as when you are booking your lodging.

5. Emergencies and bereavement fares. If you are traveling for a funeral or to visit someone who is very ill, make sure to ask the airline if they offer bereavement fares or other special fares that may apply to your situation.

This is typically a significant discount (often in the neighborhood of 50 percent) and you can generally apply frequent flyer miles to these discounted tickets, as well. You will need to be prepared to provide the airline with some important information about your situation. For example, if you are flying to visit someone who is terminally ill, you may need to provide the person's name and your relationship, as well as the name and phone number of the doctor and the hospital. If you are traveling for a funeral or memorial service, you may need to provide the airline with information about the service as well as address and phone number of the funeral home.

Some airlines will require you to purchase a ticket at full price and then provide a death certificate to claim a refund in the amount of the discount. Make sure you have the information you need before you call to book such a flight.

Many airlines outline their policies for bereavement fares on their website.

No matter what your special situation, always make sure to shop around. It is easy to check discount airfares online these days, and it's best not to assume that you'll get the best rate using one of your group affiliations. The major travel sites offer coupons and special flight rates, with new promotions released almost daily. A little time online can save you a lot of money in airfare, no matter what your special circumstances.