**<h1>Answer in Short</h1>** 

This is xapth `.//[@id=\'nosession\']/form/div[1]/input`

Which means, the xpath is trying to find out an any html element on page, which has `id` as `nosession`. Inside the `nosession` element we have a `form` with multiple `div` tags in it and we are selecting first `div[1]`. Inside first div tag we are finding for `input` element.