I have been creating webpages for about 2yrs now, but i never managed to get into creating an attractive background. I would like to know what program designers use in order to create the backgrounds that have many different pictures blended in, turning the background into one awesome picture.

Please provide me with the name of the program that is to be used for this.

What these type of pictures are called and where i can find some info on how to get started and creating them.

Thanks to all that reply