There are certain things which define a country and to me shutters is part of France. If you were magically whisked up into space and then landed somewhere and you had to identify the place you had landed in then I think the presence of shutters and the style of shutter would be quite a strong indication that you were in France a bit like window boxes with red geraniums might lead you to conclude you were in Switzerland.
Of course the shutters come in all shapes, sizes and colours. Generally in France they are on the outside of the house and are normally used on the windows but can also be found on either side of the doors. They are there for two reasons. One is security, as they can be secured from the inside and are thus quite difficult to prise open from the outside, especially if they are of a strong construction. The other reason is as a protection against the weather, being both a method of keeping the house cool from the hot sun and to keep it warm in the cold and windy winter time. They come in all colours though I have not seen any in yellow and orange. In Poitou-Charentes various shades of blue seem the most popular. I think that if you were trying to sell your property then painting the shutters a nice bright blue would certainly enhance the chances of selling and could increase the price.
Browns, greys and white can also be found but it is quite rare to find one in black. On this white shutter you can see the vertical rod (cremone) which is raised by a central handle to lock the shutter.
There are also different types of construction - most are solid but some are louvred -
Finally here is a slide show of all the shutters above plus a few more.