Blog is a specific platform where you can share your thoughts on a particular topic and you can easily share it in the web where people can comment, discuss all about their likings. It's just like a online personal diary. Blog now a days is an effective part of web 2.0 technology to spread your thoughts, either personal or business oriented, with the objective to gain lot of potential visitors for your particular topic.
Quality blog depends on quality content and how the given content is specific to your subject and depending upon it, visitors are attracted towards your blog. You can put two types of blogs for your business. One is to attach a blog section on your site and other one is just to maintain a separate blog relating to your business. Blog is reportedly the most effective platform to achieve huge traffic for your business, by authentic and updated content and interlinking your targeted keywords directly to your business. One of the tricky part of blog is the "comment" section where a reader (traffic from SEO perspective) can render his/her view and through it they can use their targeted link in the blog "signature". You can do it also by commenting to other relevant blog and with each approval of your comment will give u a targeted link (no matters if the link is no-follow or do-follow, visitors & hits only matters).
Also other great advantage of blogging is community sharing, where a blogger can join different blog communities (blog catalog, my bloglog etc.) and share their interests and ultimately gain good traffic. Another interesting part is that blog are cached by search engines very frequently and periodical blog updates boost your business rapidly by fetching added attention of all search engine bots. We all have heard about "Wordpress" blogs, which directly have +ve effect on SEO. You can easily customize your wordpress blogs through free theme provides, and you can do all SEO works (like xml sitemap, robots.txt, Meta tags set up and many more....) by installing effective wordpress plugins into your wordpress platform.It's also very easy to gain PR for your blog more faster than your normal website. These are all included in the "blog functionality" section.
In the Wordpress platform you can drastically do all you need to make your domain feasibly by even controlling the CSS structure, modifying it gives you lookups according to your choices. Even you can incorporate too many social media tools like twitter, facebook, myspace, stumbleupon, digg, dilicious etc.into your blog, which will provide you the ultimate traffic.