Plank is a simple dock. There are other popular docks like Cairo, Avant Windows Manager gDesklets, KXDocker available.
I have installed Plank on Mint Cinnamon Desktop by running the below commands on terminal:
sudo add-apt-repository ppa:ricotz/docky
sudo apt-get update
sudo apt-get install plank
It is very easy to use and as seen in about pic, I have added some of my favorite and frequently used apps to Dock