Knowing historical context allows you to see how popular house designs expressed the taste, the economy and the technology of their times.

• Italianate, 1860-1885

Illustrations by Ed Cox

These are the Victorians you think of as "San Francisco style," usually with small porches featuring classical columns, always with multi-windowed bay fronts.

Emphasis is on vertical lines; facades are narrow and tall under a low-pitched roof. The forms and ornament are derived from Renaissance villas and palaces.

Look for wooden trim imitating carved stone, heavy cornices (roof edges) with ornate brackets and sometimes arched windows that are often topped with elaborate built up mouldings.

• Queen Anne, 1880-1910

Trim can be Classical, Tudor, lacy jig-sawn "Eastlake" or even Gothic, in endless and often lavish combinations.

The details rule. Fancy shingles, spindlework, stained or leaded glass and intricate frieze decorations make a glorious visual fruit salad.

Midtown has many smaller Queen Anne cottages, without the signature corner towers of larger models.

Raised on "flood basements," most have long entry stairways with fancy details. Almost all have steep-pitched roofs and front bay windows.

Elaborate "gingerbread" trim on porches, roof edges and around windows was always made of redwood, the ideal exterior wood.

• Foursquare, 1900-1920s

Simple box shapes are usually topped with low-hipped roofs, and most facades have full-width porches with wide stairs.

Foursquares can be trimmed in a Craftsman motif, or Prairie style (a la Frank Lloyd Wright), or even Spanish Colonial, stuccoed with tiled roof edges.

Most have California Revival detailing: Formal columns, wide (sometimes fluted) corner trim, window sashes with small panes and wide entry doors with sidelight windows. Midtown is full of these in every imaginable finish, trim and decor.

• Craftsman, 1900-1930

Craftsman themes are most often seen on bungalows, houses with low profiles and prominent roof exposures. Look for exposed rafter ends (often "birds-mouth" shaped) under wide eaves, plain large beams and heavy brackets, shingle siding, "hand-crafted" light fixtures and hardware and misshapen clinker bricks or river rocks in chimneys and porches.

Early midtown bungalows usually have more built-up detailing, sometimes with Swiss or Japanese themes. Exteriors became very plain by the 1920s.

• Provincial, 1920

Architect trained in the modern International style like to make fun of these pre-World War II escapist fantasies with labels like pseudo-Tudor, faux Chateau, elastic Hispanic, Cape Coddled, etc.

But these are usually efficient and pleasant homes, sometimes cozy, sometimes imposing and elegant.

Midtown also has many apartment buildings displaying the taste and fashion of the 1950s and '60s.

Architecture buffs in the next century will possibly find these interesting, perhaps even attractive. That will take a while yet.