The efficiency dimension refers to four important aspects related to accessibility,usability,design,and system availability.Accessibility indicates the user's ability to access the resources that the Web site offers.Usability refers to the site's ease of use,which can be define as: "the ability of a customer to find information or enact a transaction with the least amount of effort". Design aspect refers to the site's overall layout, i.e., that is well organized and structured. Finally,system availability refers to the proper technical operation of the site,although firms may not have total control of this dimension since it may well be affected by the consumer's equipment or connection to the Internet.