 Usually people stand to the right and people walk past to the left. That's the way it's always been. It's kind of like an unwritten rule. But another study's out suggesting that rule might mean one individual can move faster. But there's a trade-off. University of Maryland professor Michael Foo says if everyone follows that rule... Usually there's a lot more standers and walkers will be clogged up where the left side will be kind of underutilized.