A sensor says a brake pad has worn down to its limit. Not every car has one.
Can I keep driving?
Your brakes still work for now, but get the pads replaced soon. Worn-out pads damage the discs and take longer to stop.
What to do
Book a brake inspection this week rather than waiting.
Leave extra room to the car in front until it’s fixed.
If you hear grinding or the pedal feels odd, stop driving and get help. That can mean metal on metal.
General guidance, not a diagnosis. Warning lights vary between cars, so check your owner's manual too. If you're ever unsure or the car feels wrong, stop and call for help.