Blog is easy way to express own opinion and share information to world. If you are running any company or organisation then you must create blog and forum.
In blog update all information regarding your company updates and news.for create blog you can use any free cms like WP or Blogger.
Actually you can not show all details and company or product news on official site of company but on blog you can update any type of information .
Second one is forum. if company have not own forum then you can think once that company is not very popular . forum is for public and personal both. on company forum, user of you company’s product can share experience with your product.
If you are not company owner , simple web user then i suggest you to check any company’s blog and forum before purchase any type of product.