I spent a few years on an aircraft carrier.
LSO tells pilot to "call the ball" when he sights the "meatball" of the Mirror Landing System at the edge of the Flight Deck. "Roger Ball" is the LSO response to "I have the ball"
Pilot adjusts glideslope on the way in, LSO, aka "Paddles" then aids the pilot in lining up to "catch the wire" when the aircraft is in close enough the pilot can visually identify the motions LSO makes to keep wings level, or "wave off" to abort landing if LSO spots an issue like landing not fully extended or tailhook not properly deployed