Testing PDF

Abstract
Forth is unique among programming languages in that its development and proliferation has been a grass-roots effort unsupported by any major corporate or academic sponsors. Originally conceived and developed by a single individual, its later development has progressed under two significant influences: professional programmers who developed tools to solve application problems and then commercialized them, and the interests of hobbyists concerned with free distribution of Forth. These influences have produced a language markedly different from traditional programming languages.

Presented at the ACM SIGPLAN History of Programming Languages Conference (HOPL II, April, 1993). Published in ACM SIGPLAN Notices, Volume 28, No. 3, March 1993. Permission to copy without fee all or part of this material is granted provided that the copies are not made or distributed for direct commercial advantage, the ACM copyright notice and the title of the publication and its date appear, and notice is given that copying is by permission of the Association for Computing Machinery. To copy otherwise, or to republish, requires a fee and/or specific permission.

Reference:
https://www.forth.com/resources/forth-programming-language/

Here comes the link to the PDF

The programming language reference guide is found here:
Forth