Visio is a flow chart diagram software for Windows created by Shapeware in 1992. The company later renamed to Visio Corporation. Visio was acquired by Microsoft in 2000 and became part of the Microsoft office suite of programs.
The software kept getting new features such as floor plans, server racks, network diagrams, and much more.
There is no MacOS version of Visio, but there are 3rd party programs that can open the files.
http://visio.mvps.org/history/default.html (This link covers the history long before they made Visio, back to 1984 up to 2013)
http://www.visiocorp.info/#/pressitem/15 (Original press release for Visio 4.0)