One of the tools I will commonly use on this site is the OpenCV libraries. These are some wonderful tools that can be very useful to draw objects, display images, and to track objects. There are some very advanced functions on OpenCV, but here I will walk you through a very simple example that uses python to detect faces on a laptop.
Step 1: Install Python
This is a simple enough step. Install the windows binaries
For Windows or MAC: https://www.python.org/download/
Currently I am using python 2.7 to work with OpenCV and that is the version I recommend installing. Though if you want to do other things such as install on a Raspberry Pi you will only be able to use python 2.4.
Step 2: Running some sample Scripts
Step 3: Easy Face Detection from a laptop
Step 4: Example
Step 5: To Infinity and Beyond