A Responsive designed site has the ability to adapt to any screen size, whether it be Smartphone, Tablet, Laptop, Desktop or any other internet enabled device. You aren’t creating separate designs or Apps as done before, but one design that contains code enabling it to change based on the proportions and resolution of your screen.
Here is a quick tutorial on Designing Responsively.
What is Responsive Design?
Navigation Menu to Dropdown Menu For Smaller Screens
Using Media Queries
Videos via Awful Media