With over 90% share of the market, Google is the undisputed leader of the search engines. There are however other search engines that are worth exploring to get a different perspective of the web.
Bing
With less than 3% share Bing Search is the second most popular search engine, and powers some alternative search engines (such as DuckDuckGo and Yahoo Search).
Yandex
Yandex Search is popular in the russian speaking world.
DuckDuckGo
DuckDuckGo Search is a privacy-oriented search, and is based on Bing.
Mojeek
Mojeek Search is based in the UK and has its own index.
Marginalia Search
Marginalia Search is a specialized search engine that favors text-heavy sites that use simple html markup.
Yep
https://yep.com/ is a search engine by Ahrefs
Brave Search
AI Search Engines
Phind
https://phind.com/ for developers
iAsk
Specialized search engines
Grep.app
https://grep.app/ searches code from github
Google Scholar
Elicit
https://elicit.org/ searches research papers