https://tex.stackexchange.com/help/closed-questions explains the difference
Questions are marked
[on hold] for the first five days after closure to encourage edits and improvements to the question. If a question is edited by the original poster when it is marked
[on hold], it will automatically be placed in a review queue to be considered for reopening. If it is not reopened within five days, the
[on hold] notice automatically changes to
[closed]. There is functionally no difference between an
[on hold] question and a
[closed] one; neither can be answered until it is re-opened, but they both allow comments, votes and edits.
So yes, there is a time period of five days where a recently closed question is on hold, it will only be marked as closed after that. But there is no functional difference between the two states.
You can find more about the background behind
[on hold] vs
[closed] in Every "close" has its thorn: replace "close" with "on hold" for the first five days. The only reason behind this transition between the two states seems to be the hope to avoid the psychological effect that closed has compared to the more 'temporary' and supposedly friendlier on hold.