A Youth Hostel Card identifies you as a paying member of a hostelling organization and allows you to use Hostels at a reduced rate. American Youth Hostels (AYH), part of Hosteling International is a good organization for discount lodging around the world. Hostels provide inexpensive accommodation and available to members of any age. The accomadations are generally simple dorm-room style, but are very cheap, safe and wholesome. Hostels are also probably the best places to meet other travelers and exchange information.
Originally created to help young people of limited means to experience the world, hostels are now also open to a wide age group. Today's hostellers are just as likely to be in their thirties and bring their family by car, as to arrive alone on foot with a rucksack.
You can join your national YHA as a member, contact your national office click Worldwide Hostels for detail. Your national membership card is valid for local as well as international travel if your country is a full member of the IYHF.
Most students already have a student identity card issued by their school or university. However, these cards aren't recognized internationally. Therefore, it is necessary to purchase student ID that will be recognized wherever you travel.
The most common type of student ID card is the ISIC or International Student Identity Card, accepted in over 90 countries and carried by millions of students world wide. Officially endorsed by international organizations, national governments and student organizations, the ISIC can get you reductions in transportation prices on planes, trains, buses and ferries and savings at retails shops, restaurants and accommodation centers around the world.