... the most common used search engines
... diagnostics for various issues at net
According to news sources, roughly 700 million people visit Yahoo websites every month. Yahoo itself claims it attracts more than half a billion consumers every month in more than 30 languages. https://en.wikipedia.org/wiki/Yahoo
It was released lately in june 2009 and is Microsoft's search engine. It's user experiece is rated a third of that of google to compare it like that. But Google was online twelfe years before. https://en.wikipedia.org/wiki/Bing
Google is the most advanced and spread search engine in the web. It's automated indexing service went online back in 1997 and has the power to crawl for thousands of new Website updates every day. https://en.wikipedia.org/wiki/Google
These are smaller providers, that are mostly known by the downloads and tools they provide.
This allows you to test your Internet Speed in both directions, up- and download. It's a good tool to test wether your Internet Speed meets the specifications of your provider. Ookla is the company that provides speed measurement servers all around the globe.
This can test how much likely your emails are flagged as SPAM in the internet. Just write an email with a subject and a short message from your inbox to the email address displayed on the homepage and check your SPAM-statistics. http://www.mail-tester.com/
This is a large toolset to diagnose different problems with DNS and Email-Servers. It also allows a check, wether a Email-Server is blacklisted as a SPAM-Server or not. http://www.mxtoolbox.com/