You learned arithmetic operators (+, -, *, /, %, **) and how + concatenates strings. You used comparison operators (>, <, >=, <=, ===, !==) and logical operators (&&, ||, !).
You discovered short-circuit evaluation, nullish coalescing (??), and optional chaining (?.). These modern operators make code safer and cleaner.
Key habits: use === for comparisons, ?? when zero is valid, and parentheses for complex expressions.