If you have used lollipop version of android you see a nice ripple effect on button clicks. This tutorial is about achieving similar result, the css ripple effect using only css.
Most of the Apps contains 3 lines bar on top header when click on that icon you see a nice menu sliding from left side, what is called drawer menu. This tutorial is about implementing pure CSS drawer menu for HTML.
FontAwesome, google font and ionicons are icon fonts you can use it in your website for free. FontAwesome contains a total of 605+ icons and google material design icon contains a set of 900+ icons.