A passport stamp is an impression that immigration authorities place on a traveler's passport when entering and leaving a country. Most countries use a rubber stamp to ink the impression, but some, such as Japan, use stickers.
Many travelers view their passport stamps as badges of honor or special trophies. Highly prized stamps among travelers include Antarctica, which is hard to get to, and Burma, which until recently was closed to tourism. Other remote places for a bucket list include Easter Island, Galapagos, Greenland, Machu Picchu and the Republic of San Marino.
Some remote locations have souvenir passport stamps you can request from their offices of tourism.