A bot is a software application that uses automation to run scripts on the internet. Also called crawlers or spiders, these guys take on the simple yet repetitive tasks we do. There are legitimate bots and malicious ones. A Web Application Firewall (WAF) filters the web traffic and blocks any malicious bots, letting the good ones pass.
Googlebot is Google’s web crawling bot. Google uses it to discover new and updated pages to be added to the search engine index.