Boolean algebra, combinational and sequential circuits, minimization, number representations, computer arithmetic (fixed and floating point).
Algebra with binary operations and, or, not.
Combinational: output depends only on current inputs. Sequential: uses memory (flip-flops).
Simplifying Boolean expressions using K-maps or Quine-McCluskey.
Binary, octal, hexadecimal, BCD, signed numbers (2's complement, 1's complement).
Addition, subtraction, multiplication, division in binary; floating point representation (IEEE 754).