Ubuntu下查看已经安装的包

To list all installed packages including version and description use
dpkg -l
This should be piped to less using | less for better reading.

You may also use the following to print only the packages without version and description using
dpkg --get-selections | awk '{print $1}'
This command can easily be piped to a file for saving using > file_name

It’s also easy to count the number of installed packages using

dpkg --get-selections | wc -l

http://thehook.eu/blog/page/2/