Usability is all about making things easier for site visitors.
Poorly designed sites often drive away visitors and potential business. You may have observed on the internet that some sites are very easy to use, download fast, make you feel comfortable and give what you are looking for immediately. Most sites are just the opposite and unfortunately form the majority. You suffer as your site looses visitors and potential business. What is usability Usability is making things easier for a site visitor and a measure of effectiveness of a site.