ICOCA is a prepaid smart card used primarily for public transportation in the Kansai region of Japan, including cities like Osaka, Kyoto, and Kobe. It allows users to easily access trains, buses, and even some shops without needing cash. The card can be recharged at ticket machines and convenience stores. In addition to transportation, ICOCA can be used for various purchases at participating retailers, making it a convenient option for both locals and tourists. The card is part of the IC card system in Japan, which includes other cards like Suica and Pasmo.