Clicking on an internal document link (also known as an anchor link) navigates to a different part of the same page. This action does not create a new entry in the browser's history since you're not navigating to a new page; rather, you're moving within the current one. Therefore, the browser's history remains unaffected. 

The "style" attribute in HTML allows for inline CSS styling to be directly applied to an element. While external and internal CSS are more common for styling whole websites or large parts of pages, the "style" attribute can be used to override these styles or quickly add specific styles to individual elements without needing to edit a stylesheet. It's a way to provide specific style rules to a single element. 

The usemap attribute in the tag links the image with a specific image map defined elsewhere in the HTML document. It takes the name of the map (preceded by a #) as its value. This allows multiple areas within the image to be clickable and direct to different destinations.