When do discrete and continuous mathematics (in a formal sense) come into everyday development tasks? I don't even really know what those fields are, but I do f

When do discrete and continuous mathematics (in a formal sense) come into everyday development tasks? I don't even really know what those fields are, but I do fine as a developer. What am I missing out on by not knowing anything about them? Edit to elaborate on "everyday development tasks": some startups innovate by applying some novel algorithm (beyond well-understand and well-documented ones that anyone could implement), but many are just taking well-understood problems and solutions and doing them better. Better UI/UX, better business-model, more integrated with other platforms, etc.