Braced frames use diagonal members to resist wind and quakes. They’re fast, economical, and very stiff, but braces can limit openings or circulation in some bays.
Moment frames rely on rigid beam-to-column connections. No braces interrupt the space, so layouts stay open and flexible. They usually cost more and can be less stiff, so drift control needs attention.
Rule of thumb: mid-rise + value = braced; open layouts or facade freedom = moment.