Ever been sent a link in an email that is so long it is broken up being sent. You have to spend time cutting and pasting it back to together only to find out it still doesn't work. You try typing it in yourself to see if you can spot the mistake but again nothing.
URL shorteners take a very long link and create a redirect. You create a short URL to take the place of your huge one.
http://www.amazon.com/Kindle-Wireless-Reading-Display-Globa lly/dp/B003FSUDM4/ref=amb_link_353259562_2?pf_rd_m=ATVPDKIK X0DER&pf_rd_s=center-10&pf_rd_r=11EYKTN682A79T370AM3&pf_rd_ t=201&pf_rd_p=1270985982&pf_rd_i=B002Y27P3M