# Bash Features (Bash Reference Manual)

This chapter describes features unique to Bash. • [Invoking Bash](https://woodrowpearson.gitbook.io/code-gists/invoking-bash-bash-reference-manual#Invoking-Bash):  Command line options that you can give to Bash. • [Bash Startup Files](https://woodrowpearson.gitbook.io/code-gists/bash-startup-files-bash-reference-manual#Bash-Startup-Files):  When and how Bash executes scripts. • [Interactive Shells](https://woodrowpearson.gitbook.io/code-gists/interactive-shells-bash-reference-manual#Interactive-Shells):  What an interactive shell is. • [Bash Conditional Expressions](https://woodrowpearson.gitbook.io/code-gists/bash-conditional-expressions-bash-reference-manual#Bash-Conditional-Expressions):  Primitives used in composing expressions for the `test` builtin. • [Shell Arithmetic](https://woodrowpearson.gitbook.io/code-gists/shell-arithmetic-bash-reference-manual#Shell-Arithmetic):  Arithmetic on shell variables. • [Aliases](https://woodrowpearson.gitbook.io/code-gists/aliases-bash-reference-manual#Aliases):  Substituting one command for another. • [Arrays](https://woodrowpearson.gitbook.io/code-gists/arrays-bash-reference-manual#Arrays):  Array Variables. • [The Directory Stack](https://woodrowpearson.gitbook.io/code-gists/the-directory-stack-bash-reference-manual#The-Directory-Stack):  History of visited directories. • [Controlling the Prompt](https://woodrowpearson.gitbook.io/code-gists/controlling-the-prompt-bash-reference-manual#Controlling-the-Prompt):  Customizing the various prompt strings. • [The Restricted Shell](https://woodrowpearson.gitbook.io/code-gists/the-restricted-shell-bash-reference-manual#The-Restricted-Shell):  A more controlled mode of shell execution. • [Bash POSIX Mode](https://woodrowpearson.gitbook.io/code-gists/bash-posix-mode-bash-reference-manual#Bash-POSIX-Mode):  Making Bash behave more closely to what the POSIX standard specifies.