Logs

Harvested from trees. Logs are needed to create Wooden Planks (Sometimes just called Planks) Birch trees give different colored Logs, but they still give the standard Wooden Plank. This may be on purpose or it may be subject to change.
Found on http://www.minecraftforum.net/topic/175251-minetionary-the-minecraft-dictio

Logs

Heavy pins that are often used for practice, since they generally require more precise hits to achie
Found on http://www.superglossary.com/Glossary/Entertainment/Bowling/

Logs

Very heavy pins, up to four pounds in weight, used for practice.
Found on http://www.bowlersparadise.com/help/glossary.shtml
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