It's both, really. Knowing the correct data type won't get you anywhere if you use a language like PHP and assume that it will always correctly guess the requir

It's both, really. Knowing the correct data type won't get you anywhere if you use a language like PHP and assume that it will always correctly guess the required data type for a given problem. I find that when it comes to programmers who reach a certain level of proficiency, it doesn't matter whether they learned these things through a CS degree, or through hard knocks. I started out with VBScript and ASP 1.0. I didn't get a CS degree, but I ended up learning about floating point errors rather quickly. This lead me to learn more about data types. Similar result, different path. I ended up paying for my error, much like someone would pay for an education. There are certainly bad programmers without CS degrees who make these mistakes, but I know plenty of programmers who hold a CS degree and will consistently misuse float unless reminded to use something more appropriate.