Banners made in HTML5 are the current standard. They are used in advertising in most of the media houses and Google AdWords services.
The final banners can be made in all sizes. The usual sizes are: 728 x 90px, 300 x 250px, 336 x 280px, 320 x 100px (mobile) or 300 x 600px (skyscrapper)..
The banners can be designed in Photoshop (with layers), vector PDF document or Illustrator.
We prepare the final products for different media houses (before we start making the banners it is important to tell us where the banners will be displayed and forward any technical specification) because we know three main types:
Discount on larger quantities.
Similar to HTML5 banners there are similar rules to follow. We must receive the technical specifications, the desired document size and file size limitations. Flash banners are not that common anymore (they have been replaced by HTML5 banners).
Gif is an image format that displays the animation as a series of frames. It is used mainly for simple animations - for example displaying three different pictures.
Gif animations are not supoer smooth. With complex Gif animations the file size of the banner rises fast.