Slot booking is a process in which candidates are allowed to book an exam date and time as per their preferences. Once the slot booking process is done, candidates are able to download the admit card.

noun. a narrow, elongated depression, groove, notch, slit, or aperture, especially a narrow opening for receiving or admitting something, as a coin or a letter. a place or position, as in a sequence or series: The program received a new time slot on the broadcasting schedule.