Metrorail is a quick, clean, safe, efficient and inexpensive way of getting around Washington. Purchase a computerised fare card inside a station (base fare $1.20), although you'll probably want to purchase a fare card of greater value to make sure your trip is covered. A $5 One-Day Rail Pass is a good deal; it allows you unlimited passage for the day, after 9.30am weekdays and all day Saturday and Sunday. The Metrobus system is not as easy to use, although, with a free transfer from the subway station and 35 cents, it is certainly cheap. If you're near the Dupont Circle or Foggy Bottom Metro stations and want to get to Georgetown (one place the Metro doesn't go), keep your eyes open for a Georgetown Metro Connection shuttle bus, which costs only $1, or 35 cents with a Metro transfer.
Taxis are abundant. Diamond, Yellow, and Capitol are three of the better-known cab companies in the District. A zone system determines fares, starting with $5 for travel within one zone. Taxis charge extra for rush hour travel, for other passengers in your party, and if you phone for a cab rather than hail one on the street.