GRASS 5.x Reference Manual
This reference manual details the use of modules distributed with Geographic Resources Analysis Support System (GRASS), an open source (GNU GPL'ed), image processing and geographic information system (GIS)
NOTE: Some modules listed here are not yet available in GRASS 5.x.
GRASS development has been conducted since 1995 at USACERL, the GRASS Development Team at Baylor University, Texas and University of Hannover, Germany are now the official sites for all new research, development, testing, distribution, training, and support.
One line command reference - overview
 Database Commands
 Display Commands
 General Commands
 Grid 3D Commands
 Imagery Commands - Overview
 Miscellaneous Commands
 Models: simulation models
 Paint Commands
 Photo Commands
 PostScript Commands
 Raster Commands - [complete GRASS 4.x/5.x raster command list]
 Shell Scripts
 Sites Commands
 Vector Commands
 NVIZ2.2 visualization tool tutorial
 Commands Missing a Manual Page
Throughout the manual, module input to be explicitly entered by the user is printed in bold text. User-specified input (i.e., variables set by the user) is set in italic type. Boxed text shows information output to the user's terminal screen.