Unix Third Edition: Visual Quickstart Guide

Understanding Shells and Options

Depending on the particular Unix system you’re using, you may have several shells available to you. Table 3.1 describes a few of the more common ones. Each of these shells has slightly different capabilities and features. Keep in mind that the differences in shells do not affect what you can do in Unix; rather, they affect how easily and flexibly you can interact with the system.

Table 3.1. Common Unix Shells

SHELL NAME	FEATURES
sh	This shell, which is the original Unix shell (often called the Bourne shell), is fine for scripting but lacks a lot of the flexibility and power for interactive use. For example, it doesn’t have features like command completion, email checking, history, or aliasing.
csh and tcsh	This family ...