What is Glottalized click?

Glottalized clicks are click consonants pronounced with closure of the glottis. All click types have glottalized variants. They are very common: All of the Khoisan languages of Africa have them , as does Dahalo and the Bantu languages Yeyi and Xhosa. They are produced by making a glottal stop , which stops the flow of air, and then using the front of the tongue to make the click sound in the middle of the glottal stop.