The product is a textbook titled “C : A Reference Manual” by Samuel P. Harbison III and Guy L. Steele Jr., published by Prentice Hall PTR in 1990. It is part of the Prentice-Hall Software Ser. The book covers programming languages focused on the C language, with 384 pages of content. The trade paperback format makes it convenient for students and professionals in the computer programming field to use as a reference manual for understanding the C language.