laumann.xyz: First C tip

The very first C tip to emerge from the book Head First C:

char *cards = "JQK";	/* This variable cannot be modified */

whereas, creating "an array from a string literal, then you *can* modify" the string:

char cards[] = "JQK";	/* This one can be modified */

This means that the first form can effectively be used to create read-only strings in C. Neat! This should definitely come in useful at some point somewhere. PS. I found the book _Head First C_ and thought I'd give it a go, since I'd heard some hype about this style of learning. Would be nice if some learning would actually stick in by brain!