I heard you should use hyphens inbetween keywords in your domain name to increase SEO For example: free-hosting.com Not: freehosting.com Is this true?
Domains names have little effect on SEO campaigns, and having hyphens in domain names does not help either. So to answer your question...NO!
Domain name has no direct effect on SEO. You can use any domain you want. I boils down to your linkbuilding activities.
When we look at blog post name in permalinks, it will have hyphens between words. I don't know the same will apply for domain names. My suggestion is get a domain with that keyword is already good enough.
freehosting without hyphens is far better than the other domain with hyphen. It gives a huge weigh on SER especially on very competitive keywords. But of course, it is not the only factor search engine sees. Anyway, hyphens are still important especially to long domains.
Don't worry about the SEO quality of your domain name. You should focus on how easy it will be for a visitor to remember. Most people don't remember hyphenated names.
From an SEO perspective, it doesn't matter, since SE's know how to split up a compound word regardless of if it has a hyphen already doing it or not. Hyphenated domain names simply cannot be branded. Well, maybe they can, but it is a nightmare to do so. I'd only use a hyphenated domain for something I only want to be found via regular search - I wouldn't waste time or money advertising it, though.
A "brandable" domain is far more valuable than some keyword stuffed monstrosity - even more so if you are trying to establish a credible website. If you are trying to make a quick buck and expect a short run on the domain name, go ahead and try hyphens. Many say they help, although my analysis of the SERPs suggest just the opposite. If you are going for a long term authority site, or a legit business, go brandable. As an example, I am aware of a site that specializes in espresso machines and related stuff. Rather than something like cheap-esspresso-machines-online.com they had the foresight to use wholelattelove.com many would say that domain is too long, but hey, it sure is easy to remember! A quick check shows them top 10 for 'espresso machines' on both Google and Bing.
Hyphens between domain is more conenien to remember and also search engines love them like anything. This is my experience....
Hyphenated names are not the first thing that someone types in to the address bar. My paintball business was named Pirate Bay Paintball, now I chose a domain that had no hyphens in it because I know that no one is going to automatically type in Pirate-Bay-Paintball in the address bar. Hyphens are a great tool, but as stated above, if you're trying to build a brand, make sure you choose the right domain name. Your domain should pass the "radio test" if you advertised your business on the radio, how easy would it be for someone to remember the web address?
I would suggest NOT using hyphens in your domain names... But ALWAYS using hyphens as word separators in your folder and page names... The domain name you will won't to be short and sweet, easy to remember, easy to type. Adding extra hyphens makes it longer, harder to type, harder to remember... It's the domain name that most users will type in directly to get to your site. But most people don't remember full URLs to any page except your home page. So adding additional hyphens, using longer keyword rich filenames, etc. is not as much of an issue from a usability perspective for folder and page names since most people will go to your home page directly and then navigate to the page their looking for (or find it at a search engine).