A striped tie with a checkered shirt; tennis shoes with a tuxedo (hello John Mayer?); or painting your house bright orange.
Technically each of those combinations functions properly - you need a tie, you need shoes, and your house needs paint - but is that really how you want to look?
The same applies to the windows in your house; any window style fills the holes in the wall - but they're either the right type for the house's style or they're not.
Fortunately it's not hard to get started on picking the right style for your house, since the great majority of traditional homes in America have either double hung or casement windows.
Double hung windows are the ones with two pieces that slide up and down.
Casement windows are the ones with the cranks, and that swing outwards like a door.
Traditional house styles in America can be (very) roughly divided into a couple of broad categories that reflect their origins. A quick look should tell you which style category your traditional house falls into, and which type of window is appropriate for it.
Double hung windows on an English Colonial home
Houses with English Colonial roots typically have double hung windows. Homes with this lineage are easy to identify, as they vastly outnumber any other house style in America.
If you've been to Williamsburg, VA you've seen double hung windows on early English Colonial homes.
Casement windows are common to homes with European Medieval heritage - Tudor is the most common medieval style. They're also found in some far less numerous early 20th Century American styles such as Craftsman and Prairie, and some newer "styles" like French Country.
Casement windows on a "French Country" home
In a new home, choosing the right window style is one of the most important decisions you and your Architect will make.
In an existing home, maintaining the character of the original home can be just as critical.
Get the right windows and your house will look proper and complete...get them wrong, and well - it's like tennis shoes with a tux!