In Genesis, Noah was told to cover Noah's Ark with pitch inside and outside.
Genesis 6:14 instructs Noah to make rooms in the Ark, build it from wood, and cover it with pitch on the inside and outside. Pitch is a waterproofing substance, so the detail fits the practical need to seal the vessel against water. The Hebrew wording is related to a term for covering or atonement, creating a notable wordplay in the original text.
Pitch is not the same thing as the wood named in the verse. The passage uses a separate term for the construction material and for the coating that seals it. The traditional English name for the wood is uncertain, which is why translations differ, but the waterproofing instruction is distinct.
Later retellings may describe tar or bitumen instead of pitch. Those terms refer to related waterproofing substances in broad usage, while “pitch” is the standard concise answer for the Genesis wording.