Why is the node js require function being shown on a browser (ie client side)?

Question

Well i was going through some websites source code and i saw a require function ie) its a nodejs api for importing modules. It was listed under the webpack src section, and it had a folder named node_modules which had a bunch of "server side" js syntax !!

Answer 1

Yes the require function can be used on client side and its possible with some dependencies like browserify, require.js