Why do people confuse transgender and transvestite?

I saw this question on some other website and I thought.

WTF go ahead and post it. This question might be a hit. So I did and I am posting it because I have nothing else to do

Fun Facts:

So I did a little poking around and I found that "transvestite" was coined in 1910, the term 'transsexual' was coined in 1949, and the term 'transgender' in 1971 and the term 'trans' in 1996.

And here is something else I found out that the last two terms are both very British terms

Why do people confuse transgender and transvestite?
Why do people confuse transgender and transvestite?
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