If you are looking for traditional or local German food, look for restaurants called Gasthof, Gaststube, Gastwirtschaft, or Gasthaus. A Weinstube (wine bar) will serve local wines; Bierhalle, Bierkeller, Kneipe, Biergarten or something with Brau in the name all specialize in beer and they probably also have a few local dishes. Restaurants are required to display a menu with prices including tax outside their doors. In general you will receive a lot of food in Bavarian restaurants and the quality can vary depending on what you are willing to pay. Note that typical German restaurants almost always allow smoking; non-smoking sections rarely exist. Go early to avoid a thick crowd of smokers, or search out those rare restaurants with non-smoking rooms or sections. Although dinner at home is usually at about 7 p.m., restaurants often don't even open until 7 p.m. so dinning out can turn into a late evening. Generally, you seat yourself when you go into a restaurant. However, do not sit at a table marked Stammtisch (table for the regulars). This table is reserved for locals who meet and eat there regularly. They may ask you to move or get somewhat upset if you sit at their table. If the restaurant is crowded, it is quite common for others to sit with you at your table.
Die Speisekarte is what we call the menu, and das Menu is a fixed meal with several courses. If you ask for das Menu you will probably receive at least a three course meal so be very careful! The waiter or waitress will ask you for your drink order first. Do not expect to get water automatically; you will need to order it. Bottled mineral water in Germany usually contains carbonation (Kohlensaure). If you prefer non-carbonated water, ask for Stilles Wasser (which still may contain a small amount of carbonation). If you want tap water, ask for Leitungswasser - and be prepared for getting odd looks from your server and fellow guests! Tap water is almost never served in restaurants. Drinks will not be served with ice; many Germans actually consider drinking beverages with ice cubes strange or even unhealthy.
An Aboessen is a lunchtime fixed menu, usually with your drink included, sometimes including a soup or other starter, usually priced around 5-6. It's almost always very fast and usually pretty good.
Germans eat with the knife in the right hand and the fork in the left hand. They do not put their left hand under the table. Germans are taught as children never to put either hand under the table, as it is considered rude. When done eating, lay your fork and knife diagonally across your plate with the tip of the knife and the fork prongs pointing to 10:00. You will need to ask for the bill: 'Die Rechnung, bitte.'. German restaurants do not care how long you sit at your table and be prepared for your service to be quite slow. Usually the tip is included in the price of your meal. You are expected to round the total sum of all your costs usually to a number with a 0 or a 5 at the end. In a good restaurant, an extra 10% will be appreciated but is not a requirement. Payment is made directly at the table and handed to the waitress or waiter. Do not leave money on the table. Please note that kitchens often close by 10 p.m. even if the restaurant stays open later. It is also quite common for dogs to be in restaurants.