ubuntu/debian dpkg and apt-get

1. work with packages

dpkg
-l list of installed packeages. usefull with | grep 'name'
-r remove package
-p remove package with conf files

apt-get
remove package name
"remove --purge"/"purge" remove package with conf files

example:
apt-get purge php*;apt-get purge apache*

2. add package source

sudo add-apt-repository ppa:ondrej/php5
sudo apt-get update && sudo apt-get upgrade