Get the difference between values in textarea with value and innerHTML

Today, when you're doing a little text-moving thing, you find some features:

1, in addition to the form element, the other tags in the browser page is not writable.

2.

TextArea uses value to get the value in the current textarea and innerHTML gets the value from the beginning of the page, gets the tested discovery from the document, and when we modify the value in textarea on the page displayed by our browser, In fact, the contents of the document are still unchanged (by reviewing the elements to see the contents of the textarea) and innerHTML get the contents of the document when I change the value in the textarea on the page, there is no change in the document, And value gets the values that are displayed in the page.

Get the difference between values in textarea with value and innerHTML