This chapter is definitely one of the more interesting ones to me. I'm taking two database classes this semester, both Access and SQL, so a lot of these concepts are already a little familiar to me . I learned about the stack data structure several years ago when I wrote a CHIP-8 interpreter (in Scratch, because it was the only 'language' I knew how to use at the time) because I was interested in learning about vintage console emulation and computers in general.