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A bathroom directly connected to a bedroom is often called an en-suite bathroom. Its use is primarily intended for the occupants of that bedroom only. In French the term "en-suite" literally means "a following", in this case referring to the bathroom being part of the bedroom to which it is attached. A bathroom adjacent to or directly connected to a master bedroom in a private home is generally called a master bathroom, unless it is shared by other bedrooms or is the only bathroom in the home. An en-suite bathroom attached to two bedrooms is sometimes referred to as a "Jack and Jill bathroom". Travelers often get confused regarding different types of bathrooms when booking rooms in hotels and bed and breakfast accommodation. Some common questions relate to en-suite, "private" and "shared" bathrooms (sometimes called "facilities"). Both en-suite and private bathrooms are for the exclusive use of the occupants of a particular bedroom. An en-suite bathroom is accessed from within the bedroom, however, whereas a private bathroom is accessed from outside the bedroom but is normally adjacent or near to the bedroom. A shared bathroom is a bathroom outside of any bedroom that is shared between guests staying in two or more separate bedrooms. Although the word bathroom may be used, this room may have a shower stall instead of a bathtub. The bathroom would also normally include a toilet as well as washing facilities.

In fact throughout the 16th, 17th, and 18th centuries, the use of public baths declined gradually in the west, and private spaces were favoured, thus laying the foundations for the bathroom, as it was to become, in the 20th century. However in Japan shared bathing in sento and onsen (spas) still exists; the latter being very popular.