When pausing Minecraft, it claims to be "saving level". What does that mean? Does it have the same effect as quitting and starting again?
Minecraft saves all of your block placements, inventory status, player placement, and all other level data when you pause or close the game.
The only time it might not properly save is when the game crashes and closes forcibly. Some of your work might not get saved, and there may be some discrepancies in your inventory items.