Aldus Corporation (named after the 15th-century Venetian printer Aldus Manutius) was the inventor of the groundbreaking PageMaker software for the Apple Macintosh, a program that is generally credited with creating the desktop publishing (DTP) field. The company was founded by Jeremy Jaech, Mark Sundstrom, Mike Templeman, Dave Walter, and chairman Paul Brainerd. Aldus Corporation was based in Seattle, WA.

PageMaker was released in July 1985, and relied on Adobe's PostScript page description language. For output, it used the Apple LaserWriter, a PostScript laser printer. PageMaker for the PC was released in 1986, but by then the Mac was already the de facto DTP platform, with Adobe Illustrator (released in 1987) and Adobe Photoshop (released in 1990) completing the suite of graphic design software.

Aldus went on to offer its Illustrator-like program, FreeHand, licensed from Altsys (who also developed Fontographer). FreeHand and Illustrator competed with each other for years, through multiple releases, until Adobe acquired Aldus and FreeHand was not included in the deal (FreeHand was acquired by Macromedia at that point).

In early 1990, Aldus bought Silicon Beach Software, acquiring a number of consumer titles for the Macintosh, including SuperPaint, Digital Darkroom, SuperCard, Super3D, and Personal Press (later renamed Adobe Home Publisher). Silicon Beach was located in San Diego, and became the Aldus Consumer Division.

In 1993, Aldus bought After Hours Software and incorporated its products, TouchBase Pro and DateBook Pro, into the Aldus Consumer Division.

During the 1990s QuarkXPress steadily won ground from PageMaker, and it seemed increasingly odd that Adobe — who had created PostScript, so vital to the working of DTP — still did not offer its own page layout application. This was resolved in September 1994 when Aldus merged with Adobe. Today, Adobe's competition to QuarkXPress is Adobe InDesign. PageMaker remains available but is no longer marketed; existing PageMaker customers are now urged to switch to InDesign. FreeHand is now also maintained by Adobe after the merger with Macromedia in 2005.

Aldus developed the TIFF and OPI industry standards. The three founders of the Visio Corporation left Aldus in 1990 to create the product that later became known as Microsoft Office Visio.