There was a time, quite recently in fact, when the most important attributes of buildings were their aesthetic qualities, fitness for the intended purpose, and structural integrity. However sustainability objectives - paying closer attention to the soundness of the architecture from the perspective of the environment - are quickly becoming the overriding factors in contemporary home plans.
Ranch style architecture originated in the United States in the 1920's, and it became very popular after World War II as cities expanded into suburbs and inexpensive tract homes were needed by a growing populace. Ranch style houses are most popular where land is inexpensive and the weather is mild, since these homes particularly lend themselves to outdoor living. The low, earth hugging look with clean, modern lines of the ranch style is derived from Frank Lloyd Wright's prairie style architecture.
Nowadays cottages are often used as summer or weekend getaways - often by lakes or the seaside - by urban dwellers seeking to escape the noise and rat race. They are often built as rental properties in popular tourist areas. But usually when people think of a cottage they mean a rural dwelling in the traditional English country cottage house plans style with stone or stucco siding, asymmetrical lines, one-and-a-half stories high, and with hip roof and steep gables - the overall impression being a cozy, storybook appearance.
Modern home plans are created en masse to suit the needs of people who don't want to customise the design of their new home. However, if you have chosen to customise and personalise your floor plan, you can do that too as long as you are prepared to tell the architect what you want. Professional architectural services cannot be replaced when it comes to building a home, so the matter is just to choose the one that suits you.