Carcassonne is a game set in medieval France where the goal is to accumulate more points than your opponents by controlling farms, roads, cities, and cloisters. The rules are very simple: every turn you randomly pick a tile and add it to the board, creating roads and buildings as you go. To control these various features, you place your 'followers' on the tiles as you play them. However, you have only a limited number of followers and can retrieve them only when you complete a feature, except in the case of farmers. Farmers are irretrievable but are important for winning points at the end of the game. Thus gameplay is a combination of luck, placement, completions, and interfering with your opponents. The game is for two to five players and takes approximately 45 minutes to play. Carcassonne also has many expansions that you can buy separately to add complexity to the game.
The pros: easy learning, reasonably short playing time, and fun activity. The cons: farms are tricky to understand at first, and people who are good at tracking probabilities will have something of an advantage. I find this game to be cleverly designed and a lot of fun.