Which tool is commonly used to straighten hair?

I've heard of them referred to flat irons before.

Just put your head on the ironing board to do it . Of course if you want curly hair you have to use a blowtorch . As much nonsense as this question . A flat iron is for smoothing clothes. Hair straighteners for straightening hair ( strangely enough) and I’ve never heard them called flatirons.

I thought a flat iron is what you use to iron clothes with!