I'd encourage you to write some code, too. There's a lot of intuition you gain by manipulating the bits that you can't get by reading. You may think you know what a pointer is, but until you've had to debug a double-free segfault or a memory leak, it's hard to understand the ramifications of the concept. The standard string handling functions look trivial in documentation, but when you actually use them you'll find yourself forgetting to add null bytes or not realizing that some of the functions mutate the string you're working on. I'd argue it's that process of figuring out how to make things work that gives you the famed understanding of how computers work.