Students need to rely on several sources of money (ATM/debit card, credit card, cash) to cover expenses while abroad. This will ensure that if one of your means for accessing money fails, you will not be stranded without money. Also, the amount of money you can access through any one source may at times be subject to limitations, so you will want to have a second source should you need a large amount of money immediately (e.g., rent).
Depending on the country, ATMs are common in cities and at most major airports, where you can use a credit or debit card (be sure you have an internationally valid PIN), less so elsewhere. But they are also subject to breakdowns, fraud, and other scams. Travelers are finding that the magnetic strip on the reverse of most U.S. credit cards is not enough, as an embedded chip is required to make purchases at some self-serve locations (like bus ticket kiosks). The chip technology is becoming mainstream in the U.S., and you should inquire with your credit card company to acquire one prior to departure. Another alternative is purchasing a prepaid microchip smart card (through companies like Travelex).
Transferring money is also growing in popularity and one resource for comparing the different ways to transfer money can be found on the Consumer Affairs website.
Converting dollars is possible at banks, exchange houses, and/or hotels. Be sure to have newer bills in excellent condition. Traveler’s checks can be inconvenient, since many establishments do not accept them, fees are assessed for converting them, and you are often limited to cashing them during banking hours only. Depending on your location, you may be able to open a local bank account. Meanwhile, you may wish to exchange some money (~$200) prior to your departure from the U.S. so that you don’t have to concern yourself with these matters immediately upon arrival. You will receive further information on accessing money specific to your host country in your country-specific handbook.