A Rolodex is a rotating file device used to store business contact information (the name is a portmanteau word of rolling and index) currently manufactured by Newell Rubbermaid. The Rolodex holds specially shaped index cards; the user writes the contact information for one person or company on each card. The cards are notched to be able to be snapped in and out of the rotating spindle. Many users avoid the effort of writing by taping the contact's business card directly to the Rolodex index card, or a plastic or vinyl sleeve in the shape of a Rolodex card to place the business card within. Some companies have produced business cards in the shape of Rolodex cards, as a marketing idea.
The Rolodex, invented by Arnold Neustadter and Hildaur Neilsen in 1956 and first marketed in 1958, was an improvement to an earlier design called Wheeldex. Neustadter's business Zephyr American invented, manufactured and sold Autodex, a spring-operated phone directory that automatically opened to the selected letter, Swivodex, an inkwell that did not spill, Punchodex, a paper hole puncher, and Clipodex, an office aid that attached to the stenographer's knee. Memex, a sort of conceptual precursor to hypertext, borrowed the ex suffix.