In popular travel destinations like Bali and Jakarta accommodation options run the gamut, from cheap backpacker guesthouses to some of the most opulent and expensive five-star hotels and resorts imaginable.
Off the beaten track, though, your options will be more limited. Probably the most common lodging choice for backpackers is the losmen, or guesthouse, which also go by the names wisma or pondok. Often under US$15/night, basic losmen are fan-cooled and have shared bathroom facilities, usually meaning Asian-style squat toilets and mandi water tank baths, from which you ladle water over yourself do not enter one!. Very small losmen, essentially homestays or rented rooms, are known as penginapan.
The next step up on the scale are cheap Chinese-run hotels, usually found even in the smallest towns and cities, typically near transport terminals. These may have little luxuries like air-conditioning and hot water, but tend to be rather depressing otherwise, with tiny, often windowless rooms.
By law, all hotels have to display a price list daftar harga. You should never have to pay more than the list says, but discounts are often negotiable, especially in the off season, on weekdays, longer stays, etc.