Digital Logic
Most Significant Bit (MSB)
The bit position with the largest weight in a binary number, typically the leftmost bit.
Detailed Explanation
In an N-bit number, the MSB is bit N-1 with weight 2^(N-1). For signed two's complement numbers, the MSB indicates sign (0=positive, 1=negative). The MSB changes least frequently in a counter.
Sign extension replicates the MSB to preserve value when widening a signed number. MSB-first transmission sends the most significant bit first (opposite of LSB-first).