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So that you know, Vellum [1] is the name for an often used and well known piece of software used to write books. It's an absolutely fantastic piece of software. Vellum has been around since 2015. [2]
Vellum (the word) is prepared animal skin or membrane, typically used as writing material. [3]
[2] https://web.archive.org/web/20151112064306/http://vellum.pub...