<h2>Shebang</h2> <pre><code>#!/bin/bash</code></pre> <h2>Comments</h2> <pre><code># This is a comment</code></pre> <h2>Strings</h2> <pre><code>STRING="Hello World" 'Single and multi-line strings are supported.' "Single and multi-line strings are supported." cat << EOF Here-Documents are also supported EOF</code></pre> <h2>Variables</h2> <pre><code>echo $STRING args=("$@") echo ${args[0]} ${args[1]} ${args[2]}</code></pre> <h2>Keywords</h2> <pre><code>for (( i=0;i<$ELEMENTS;i++)); do echo ${ARRAY[${i}]} done while read LINE; do ARRAY[$count]=$LINE ((count++)) done if [ -d $directory ]; then echo "Directory exists" else echo "Directory does not exists" fi </code></pre> <h2>Some well-known commands</h2> <pre><code>crontab -l -u USER | grep -v 'YOUR JOB COMMAND or PATTERN' | crontab -u USER - groups user1 user2|cut -d: -f2|xargs -n1|sort|uniq -d wget -q -O - http://www.example.com/automation/remotescript.sh | bash /dev/stdin parameter1 parameter2 sudo dpkg -i vagrant_1.7.2_x86_64.deb git pull origin master sudo gpg --refresh-keys; sudo apt-key update; sudo rm -rf /var/lib/apt/{lists,lists.old}; sudo mkdir -p /var/lib/apt/lists/partial; sudo apt-get clean all; sudo apt-get update</code></pre>