Extensions are suffixes, such as .com or .net, at the end of web addresses. These can have specific uses, so make sure to choose one that works for your business. The .com domain extension is far and away the most popular, but it can be tough to get a short and memorable .com domain name
because it’s been around for so long.
A bevy of new generic top-level domains — like .app, .photography, .nyc and .guru — offer a great opportunity to register short and highly relevant names. And here are some other top extensions and how they’re often used:
.co : an abbreviation for company, commerce, and community.
.info : informational sites.
.net : technical, Internet infrastructure sites.
.org : non-commercial organizations and nonprofits.
.biz : business or commercial use, like e-commerce sites.
.me : blogs, resumes or personal sites.
A tip: You don’t need to build a website for every domain. Just forward any additional domains to your primary website.