When Coders and Programmers are working on their code it often times is much easier to read for humans with spaces and comments about sections of code. Computers do not need any of these spaces or comments and therefore can process the data much quicker without them.
For WordPress users, there are plugins that provide a function that strips out all of the unneeded spaces. Essentially, all the work is done behind the scenes and takes little time to implement.
David writes for a couple different websites that work with hosting and consumer reviews. He brings real-world application to harder to understand concepts in order to help people learn about specific subject matter. He also knows HTML, CSS and PHP to help out with building and configuring sites.