Re: An example ?
"With drive-by infections, it is enough to simply visit a website to infect a computer with malware. Visitors don't need to start a download or install anything - the website does this automatically!"
My browser will not automatically download anything, without asking me where it should save it first. What kind of browser are you using that would do this? An idiotic one by the sound of it.
"Yet If a browser has a relevant safety gap, such scripts can access a user's computer directly. This therefore enables malware to move from the server to the browser, and via the security gap to the user's computer, without any conscious action by the website visitor at all."
Again, it's a problem with the browser, and you should change your browser.