Draw.io is a free Flowchart and diagram creation software for Windows, Linux, macOS and your browser

Flowcharts are incredibly useful diagrams to explain process flows.  But how do you make them using a computer? Microsoft Office or Libre Office can be used to create flowcharts. But an application like Draw.io that specializes in drawing diagrams can be a better option.  

https://www.ghacks.net/2019/09/07/draw-io-free-flowchart-creation-software-windows-linux-macos/