What is invisible zipper for?

Invisible zipper is usually behind its tape whose color matches with its slider and the clothing (or other articles.) Though zipper’s kind varies, somehow some articles just don’t look good with zippers. Thus invisible zippers come into great use in some women apparel, such as ceremonial dresses, pants and skirts.
If you love to make clothing or bedding by yourselves and don’t want zippers exposed, this video might be very helpful. Even if invisible zippers don’t come in handy, you can still “sew” invisible zippers.

(Quoted from: http://www.youtube.com/watch?v=RneYzsqOyD0)