As you progress in your software engineering career, the level of abstraction of the knowledge you use on a daily basis gets higher and higher. The academic CS

As you progress in your software engineering career, the level of abstraction of the knowledge you use on a daily basis gets higher and higher. The academic CS concepts underpin everything, but rarely do you need to go below a few levels of abstraction to solve problems in the real-world (at least in most non-cutting edge jobs). For example, to build a web app the level of abstraction your job requires is probably on the level of web frameworks and API's. Now and then you'd need to understand the web protocols. Rarely would you need to write software involving the low level transport mechanisms. Rarely would you inspect packets yourself and perform verification and decoding through pen and paper. Even rarer still would you need to use maths to design the signaling procedures between hardware components. Point being that it's normal to now know off-hand all the lower level CS stuff, but you recognize the patterns, and in the rare occasion you need to actually access all that information you wouldn't be at a complete loss.