“Retail salespersons and cashiers were the occupations with the largest employment in May 2013”: BLS.

The top ten of U.S. Occupational Employment Statistics for May, was released today by the Bureau of Labor Statistics. Office and Administrative support related occupations counted almost 22M people in the field. Sales men and women are second with 14M. Americans like to eat outside home and having their food prepared by specialists. Food preparation and serving related occupations made up to almost 12M people employed in restaurants and related establishments. On the fourth place are crowded field of transportation and material moving occupation with 9M.
On the bottom of the list is farming and fishing related occupations. A little bit more than 400K people are employed by such type of activities.
Computers and mathematical occupations type of establishments employ 3.6M people.

In terms of who is making more money Management occupations win the first place, seconded by legal occupations which make an average of 110K and 99K respectively. Computers and mathematicians are in third place with a mean wage of 82K.
Although Food preparation and serving related occupation represents the third largest employment industry in US, employees make the lowest average wages: 21K.