My question is: Are all land (couldn't find a better word

)floating on the ocean?
Japan and Hawaii is a piece of land that is floating on top of the ocean, right?
Then is the United States, Canada, Europe, and all large land floating on top of the ocean or does the land reach all the way to the bottom of the ocean surface?
I probably lost some of you. If you understand what I am saying, please post whatever knowledge you have or if you're confused, ask me questions.