While the Torah does not provide much detail regarding Tzitzit and Tallitot, there is a considerable amount of discussion in Jewish Legal Texts regarding the shape of a Tallit, the method of trying Tzitzit strings, materials used and colors, if applicable.
Ashkenazi Tallitot are the most easily recognizable Tallitot with their black stripes and large size. These Tallitot generally have an Atara, a piece of fabric at the top edge that marks it as being such, at the top. The Atara is usually decorated with floral patterns, images of Jerusalem, Stars of David and other Judaica. Names are also frequently embroidered into the top as is the blessing said when putting a Tallit on. The left and right sides of the Tallit have a series of knots running along their length between the top and bottom corners.
Ashkenazi Tallitot also generally have black stripes that run along the Tallit’s entire length. The black stripes, according to many Jewish legal authorities serves as a reminder of the Tekhelet, the blue colored string that was not used by Jewish in their Tzitzit for over two millennia. However, it should be noted that Jewish Law does not provide a require color for Tzitzit other than the Tekhelet string and therefore the striped pattern may be any color and can feature any design or image.