Blogs can be a means of getting your writing noticed on the Web. Some writers have gotten book deals based on work that started as a blog (a famous example: Julie Powell's Julie and Julia which began life as the Julie/Julia Project blog). Already published authors also use Blogs as a means of promoting their careers. There are many free blog tools available on the web.
Many authors also have their own web sites in addition to or instead of blogs. There are any number of hosting services that offer web server space for a fee, some, like WordPress, offer a limited amount of space for free (though in some cases the free sites come with ads). Web page editors don't necessarily require that you know HTML code, though it does help to know at least some of this markup language because you can more easily customize your web page or blog if you understand what's going on under the hood. Some helpful resources for getting started:
There are so many blogs and web pages out there that it's no longer enough to have a blog or a web site to get noticed. Social media tools like Facebook and Twitter can be used to direct traffic to your blog or web site. Tell your Facebook friends to vist or "like" your blog, Tweet your web site's URL asking followers to visit. Hopefully not only they will visit, but their "friends" or "followers" will come along. Some potentially helpful resources on this topic: