There is no hot water coming from tank. Tank is lit. but no water going to faucets

there is no hot water coming from tank. tank is lit. but no water going to faucets

Is water going into the tank? Is the cold water supply available? Do you have heat trap nipples(see image) installed on the inlets? How old is the heater? Your house? What kind of piping go you have? Did this come on suddenly or did it happen slowly? I need more details in order to help. Back to you, Tom