A strip mall is a small,
arcade-like commercial development, consisting of a row of multiple (usually connected)
storefronts, typically set just off a
highway or other major
arterial road on a small lot with limited parking spaces. A strip mall usually contains somewhere between 4 and 10 distinct storefronts, though one section of road may feature multiple strip malls.
Strip malls typically play host to small or specialty retail stores, restaurants, and some service businesses like hair salons, dentists' offices, and the like. Less customer-based tenants like offices, churches, or government agencies are rarer but not unheard of. Strip mall businesses are usually small, privately operated "mom and pop" enterprises - cheaply constructed, built on land ill-suited to anything else, and visible to the thousands who drive by every day, strip malls are an attractive location for those trying to keep startup and advertising costs to a minimum. Of course, the downside to attracting small businesses is that a lot of small businesses fail, and turnover is relatively high in strip malls. Likewise, due to a shifting economic situation, new roads or development, or simply bad location, it's possible for entire strip malls to flounder. Some chain stores such as Blockbuster, as well as a few more "downmarket" chains, are often found in strip malls, though many other chains find the locations limiting or unattractive, and the corporation or franchisees typically have the resources to locate elsewhere. Shopping developments with a supermarket, an "anchor" or "big box" store, or with an actual parking lot, are generally not considered strip malls, but rather shopping centers, although the relationship between the two terms is not precisely defined and the former may be considered as a subset of the latter.
The strip mall in its modern form is thought to originate in, of all places, Kansas City in the 1920s, although of course it draws on earlier ideas and principles. In its most fundamental form, the strip mall is a reflection of ancient commercial principles - the presence of a road means that a reasonable amount of people find it worthwhile to pass by with some regularity, and at any given time, at least a few of them will happen to want to buy something. In the modern day, in a world of single-use zoning, large roads often reflect the presence of nearby residential communities, and given the separation of residential and commercial areas, convenience of location may be a significant advantage.
While there is some variation in strip mall appearance, with some bearing facades representing a variety of styles and themes, the basic architecture remains more or less uniform - simple one story buildings constructed with sturdy materials such as brick, cinderblock, or metal and divided into narrow but relatively deep units. This architecture maximizes usable space while keeping real estate costs low, a vital concern, given the typically slim margins and low capital reserves on which many strip mall businesses operate, while enabling the building's owners to create (and rent) as many units as possible facing the street. The buildings usually front a sidewalk, many times with an awning or overhang of some sort, and a significant amount of each storefront is glass, which brightens the interior (especially given the typical lack of other windows), and allows merchants or other businessowners to display their wares or put up posters and other advertisements. The rear of the building typically is a flat, undecorated wall with doors for employee entrance, rudimentary loading/unloading facilities, and dumpsters. Individual businesses typically have large signs above their storefronts, ideally visible from the road, and may have individual signs closer to the road, in addition to the standard strip mall sign which typically lists all tenants and, occasionally, a name for the mall as a whole, which no one will ever use. A store's individual signs often cost more than the floor space itself, understandable given the low-cost construction and location and need to attract customers and differentiate itself from other, similar stores.
The strip mall is a favorite target of cultural, architectural, and personal scorn. Critics find them unsightly and unattractive, assigning them part of the blame for the death of the downtown shopping district and the industrial world's by now well-established dominance of the automobile. Though not all share the opinion, and fewer still will openly say so, many disdain them as proletarian and too unapologetically commercial. In their defense, I find strip malls less a cause of ugliness, blight, automotive reliance, or poor design than a reaction to these problems (and to some extent to attempts to solve these problems), and in many ways the best possible response to a given situation.
First, it is a little ridiculous to "blame" strip malls for their location or character. Between the drive to preserve the historical and architectural character of traditional city centers and the heavy development which saturates the surrounding areas, often with purely residential neighborhoods, space (and parking) is limited in the downtown market and small businesses are priced out. On the other hand, the massive shopping centers and malls which are designed as a destination unto themselves are often ill-suited for strip mall-type businesses. However, the development of major highways, necessary to modern transportation, has created large, narrow, easily accessible swaths of land, undesirable for housing purposes due to proximity to heavy traffic. These unwanted buffer zones are useless for anything but light commercial development. Viewed in this light, strip malls are a clever, innovative way to resolve several problems at once.
As for aesthetic considerations, it is freely yielded that yes, for the most part strip malls are uninspiring, utilitarian pieces of architecture. They're quite unpretentious, really. If they look run-down, it's probably because they are - as mentioned before, strip malls and the businesses which occupy them are generally strapped for cash, and may not be in a position to keep up with architectural trends, or even basic maintenance. When an entire mall fails, as the lot it is built on is likely well-suited for nothing else, and the location has already proven incapable of supporting a strip mall, these properties are rarely bought or renovated, and the shell of a failed strip mall will often remain for years after the fact.
In short, the ugliness of strip malls is a function of their position in the economy. The flip side of this is that it's this very cheapness that allows strip malls to support niche, "mom and pop", and inexpensive stores, which save us all money, and may be indispensable to low-income families. Like "affordable housing", it may not be attractive, but it's probably better for us all that they're there.