Originally, a word processor was a simple package designed to enter text, swiftly and efficiently, with a minimal set of aesthetic options - often limited to bold text, italicising and underlining.

In more recent times, a word processor often includes more precise layout tools, tables, columns, image support and so on.

Modern "word processors" are sometimes referred to as word publishers, since the original definition of a word processor is a package to facilitate the entry of text.

StyleWriter is a plain English editor for authors. The company offers a free 30 day trial of the product.

See also: Official website

There are a few types of word processors that can be used on a computer. Most of these software packages need to be installed on a personal computer, but others are "online" applications that on almost any computer in a web browser(Internet Explorer, Firefox, Safari, etc) . Below is a breakdown of a few of these different types or word processors.

Free/Open Source
AbiWord (Linux/Macintosh/Windows)
OpenOffice.org Writer/Word processor (Linux/Macintosh/Windows)

Commercial Products
Corel WordPerfect (Windows)
iWork Pages (Macintosh)
Microsoft Word (Macintosh/Windows)
Microsoft Works (Windows)
StarOffice Writer (Linux/Sub Solaris/Windows)

Online Applications
Google Docs - http://docs.google.com/
ZCubes - http://home.zcubes.com/
Zoho Writer - http://writer.zoho.com/