Wiktionary
alt. 1 (context Internet English) A book that may be read via the Internet 2 (context computing English) Any of several portable computers (or similar) that has access to the Internet and is primarily used to read such books n. 1 (context Internet English) A book that may be read via the Internet 2 (context computing English) Any of several portable computers (or similar) that has access to the Internet and is primarily used to read such books
Wikipedia
A prominent use of the word webbook is as portmanteau of web and notebook computer to mean a class of laptop computers such as the litl, Elonex and Coxion webbook computers.
Webbook may also refer to books that are available in HTML on the web. Examples of webbooks include the Webbook of African Language Resources. and the NIST Chemistry WebBook, a scientific database of chemical properties maintained by the National Institute of Standards and Technology.
The word may also refer to The WebBook Company of Birmingham, Michigan, which announced plans to deliver a Net computer based on the PSC1000 RISC processor (then and now also known as the ShBoom) designed by Charles H. Moore.