Without question the most famous design that Adidas use upon their footwear and apparel is the 3-Stripes design. Adidas began making footwear before they made apparel: they began releasing shoes with the 3-Stripes design in the early 1950's - after purchasing the design from Karhu sports - and released their first tracksuit (apparel) with the 3-Stripes design in 1967. Generally speaking, the 3-Stripes design is an overlaid piece of fabric that is stitched onto the base fabric; therefore, the 3-Stripes design is referred to as the 3-Stripes overlay.
The 3-Stripes overlay comes in two configurations: a jagged edge and a straight edge. The more common of the two is the jagged edge. The fabric used in the overlay can be suede, leather or canvas, but is usually suede or leather. As you can see from jagged edge image above, each overlay is usually stitched with 2 lines in the centre of the overlay; although some overlays are stitched at the top, as with the other image (uncommon). The 3-Stripes overlays are used in the vast majority of heritage products, but it is being used less, or more subtle, in modern Adidas footwear.