Yes, you can understand just fine because of context. But only because of the context. Were you to see the word by itself, you'd think of them by their specific meanings. "They're" by itself is a contraction, and is actually "They Are". "There" is a reference to a different location. And "Their", is a possessive, dictating ownership in reference to an entity. These do not all mean the same thing, and are spelt differently to demonstrate a visual distinction. It's just bad luck that they happen to all sound the same, such as how Homophones are. Sea yew ones bee-comb re-spec fool UV core-act spilling. [spoiler]bait worked, good job[/spoiler]