Before the Industrial Revolution and the rise of factory work in the late 1800s, most people were self-employed farmers or artisans. By the 1900s, however, most people were employees. The vast proliferation of consumer products in the 20th century led to the creation of hundreds of jobs that had not previously existed.

Factory Work Anchored the New Industrial Economy

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Factory jobs in the 1900s were typified by assembly lines of the automobile, steel and other “rustbelt” industries. In the first decades of the century, factory employment offered minimal financial security, and the robotic nature of the work was famously parodied in the popular Charlie Chaplin movie “Modern Times.” However, beginning with the Great Depression, the rise industrial unionization dramatically increased the rewards of factory labor. By the 1950s, unionized factory jobs paid high wages with generous benefits and elevated millions of Americans into the middle class.

Secretaries Became an Indespensible Adjunct to Management

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In the 1900s, women increasingly took over the clerical work that was formerly done by “office boys.” It was the only job women were allowed to do in a company, and they were allowed to do it primarily because they could be hired for lower wages. The modern secretary’s job eventually entailed doing virtually everything for managers except their actual job. A standard mid-century textbook for secretaries describes a seemingly endless variety of tasks that she was expected to do: use the telephone expertly, handle her boss’s travel arrangements, manage his personal funds, ghostwrite letters for every possible occasion, reserve theater tickets and decorate the office.

Salesmen Transitioned from Snake Oil to National Brands

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The 1900s saw the transition of the sales person from disreputable huckster to respected professional. Most small manufacturers employed sales personnel to call on their limited market, and manufacturers of national brands typically had sales offices in cities nationwide, each with a sales force that was responsible for a regional territory. For much of the century, knowledgeable sales people were also an important feature of retail stores, though that gradually changed as self-service became increasingly common. Among the general public, salesmen -- the profession was overwhelmingly male -- continued to be viewed with a measure of skepticism, and received unglamorous treatment in the arts -- the novel “Babbitt” and the play “Death of a Salesman,” are particular examples. In business circles, however, the salesman became a glorified figure, with a huge inspirational literature devoted to the craft.

Cashiers Were Everywhere

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The cash register was invented in the late 1800s, and by the 1900s almost every organization that conducted business with the public had one. Department stores, supermarkets and other retailers soon became the source of employment for millions of cashiers. In retail management, it became conventional wisdom that cashiers should greet the customer by asking if they found everything they were looking for and invite them to return to the store at the conclusion of the transaction. For much of the century, supermarket shoppers also expected their cashiers to call out the price of each item as it was rung up, though this ritual became obsolete by the 1980s, when mechanical cash registers were replaced by computerized scanners, which took over the job of entering the prices.