Studies have shown that the color blue is preferred by men and women alike. It has a soothing and calming effect. Also gives a very professional feel when used
as backgrounds. For this reason, alone many prefer to use plain blue backgrounds.If you go online you can find various shades and variations available in such backgrounds. Most of them are of good quality and you will be able to edit them as per your liking. You can use Photoshop for the editing and can impress all.
Some are also available in PSD format which is easier to use. You can use them as your desktop wallpapers, as your web page or blog post with plain blue backgrounds. This would make the content look more amazing and stand out clearly.
Plain Blue backgrounds are known to make the text more visible, it complements the foreground essentials, it gives a more neat and accurate look, it gives your design a balance, brings in a minimal and yet alive style and lets you distinguish multiple areas.
For the above reasons, blue backgrounds have made a niche for itself in website design. These backgrounds make more sense than a busy one. This proves that just simple backgrounds can make a statement in themselves.