Automatically showing bottom of a textarea

I am making a chatbot and I want to know how I can automatically arrive at the bottom of the textarea. Let me explain better. When the text reaches the bottom of the textarea, it goes lower, and the scrolling bar appears. I want every time the page loads to go to the bootom of the textarea. I am making it so that every time a user says anything, the page reloads and the whole conversation is printed in the textarea. I want to be able to automatically reach the bottom on each page load. BTW I mean in HTML or Javascript, people, not C++.