# Engineering ---  --- ## Modules Modular code is code which is separated into independent modules. The idea is that internal details of individual modules should be hidden behind a public interface, making each module easier to understand, test and refactor independently of others. --- ### Core Modules Node.js has several modules compiled into the binary. 1. http 2. url 3. querystring 4. path 5. fs (file system) 6. util --- The core mo