The time it takes for mail to reach its destination varies based on the method of delivery and delivery location. Electronic mail is usually delivered in seconds, but if the server is slow, it can take several hours to reach the recipient's email box. Postal mail delivered through the United States Postal Service can arrive on the same day or take up to eight days for domestic transport.
The greater the distance mail travels, the longer it takes to reach its final destination. In addition to the USPS, all of the major mail-delivery companies, such as FedEx, UPS and DHL, offer overnight delivery for an increased rate. Currently, the USPS offers five mail-delivery classifications, including media mail, standard post, first-class mail, priority mail and priority mail express. Priority mail express is the fastest and most expensive USPS method. Overnight mail, which takes less than 24 hours in some cases, began in 1981. Frederick W. Smith, the founder of FedEx, is touted as the creator of the overnight mail service. It is rumored that he received a "C" on an economics paper he wrote while attending Yale University. The paper outlined how a company could send mail anywhere in the world within 24 hours.