Useful variables and functions to use in your PS1 terminal prompt string.

aliases.sh

# Common Aliases
alias c='clear'
alias ..='cd ..'
alias cd..='cd ..'

# Self-referencing
alias egrep='egrep --color=auto'
alias fgrep='fgrep --color=auto'
alias grep='grep --color=auto'
alias l='ls -CF'
alias la='ls -A'
alias ll='ls -lAh --color=auto'
alias ls='ls --color=auto'
alias mkdir='mkdir -pv'
alias nano="nano -AESm --tabsize=4"
alias rm='rm -I --preserve-root'
alias vssh='vagrant ssh'
alias vsync='vagrant rsync'
alias wget='wget -c'

# Shortcuts
alias fuck='sudo "$BASH" -c "$(history -p !!)"'
alias fucking='sudo'
alias update='sudo apt-get update'
alias upgrade='sudo apt-get upgrade'
alias dist-upgrade='sudo apt-get update && sudo apt-get upgrade -y && sudo apt-get dist-upgrade -y'
alias install='sudo apt-get install'

PS1.sh

# Inputs.
SHELL_NAME="\\v"
TERMINAL="\\l"
EXIT_CODE="\$?"
USERNAME="\\u"
WORKING_DIRECTORY="\\w"
DIRECTORY_BASENAME="\\W"
NEWLINE="\\n"
HOSTNAME_FULL="\\H"
HOSTNAME_SHORT="\\h"
PERMISSION_INDICATOR="\\$"

# Formatting.
TEXT_BOLD="\[$(tput bold)\]"
TEXT_NORMAL="\[$(tput sgr0)\]"

# Colours.
EARTH="\[\033[38;5;58m\]"
RED="\[\033[38;5;160m\]"
DARK_GREY="\[\033[38;5;237m\]"
GREEN="\[\033[38;5;34m\]"
LIGHT_GREY="\[\033[38;5;249m\]"
CYAN="\[\033[38;5;39m\]"
WHITE="\[\033[38;5;15m\]"

# Git Branch Detector
function parse_git_branch () {
    # Make sure that "color.ui" in "~/.gitconfig" is NEVER set to "always". Bad things (colour overflow) happen.
    git branch 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/ (\1)/'
}

export PS1="$RED{$TEXT_BOLD$EXIT_CODE$TEXT_NORMAL$RED}$DARK_GREY: $GREEN$USERNAME$WHITE@$TEXT_BOLD$GREEN$HOSTNAME_FULL$WHITE$TEXT_NORMAL: $LIGHT_GREY$WORKING_DIRECTORY$EARTH\$(parse_git_branch)$WHITE$PERMISSION_INDICATOR\n$CYAN$TEXT_BOLD>$WHITE $TEXT_NORMAL\[$(tput sgr0)\]"

Place this inside your ~/.bashrc file, then either reopen the terminal or reload with . ~/.bashrc to see the updated terminal prompt.
Always make sure the PS1 string ends with $WHITE$TEXT_NORMAL so the text you type into terminal is normal white text (colours and formatting will overflow from the prompt string).