I would like to make this warning go away , hopefully by fixing some problem I have: rl.js|19| jshint warning: Redefinition of 'screen'. Here is the tutorial I'm working on: http://gamedevelopment.tutsplus.com/tutorials/how-to-make-your-first-roguelike--gamedev-13677 Here is a gist of code I'm working on from the tutorial. https://gist.github.com/5588dcb8cb44d19137e0 So my question is what is wrong? Why am I getting the above warning and how can I avoid having my linter complain?