A Journey Through PHP Internals

In everyday work, it’s easy to forget just how many things are happening under the hood, how many concepts are abstracted away to make our code run and make it run efficiently. It wasn’t always the case—at first, there were languages we now call “assembly languages”—designed to faithfully represent what the CPU will execute, and one had to write these crude lines of machine instructions to make computers execute anything at all. Eventually, new languages emerged which abstracted away a lot of concepts and allowed programmers to focus on the code rather than on the machine for the most part. Among these languages were C and C++, which to this day underlie many other more abstracted languages like PHP, Java, Ruby, Python, and many others.