These days, the answer is they can be two separate things or they can both be part of your website.
A few years ago, blogs and websites were two very different things. Blogs were often a personal online diary (like my travel journal) and websites were a company’s online brochure or shopfront.
The online world has evolved very quickly in the last few years and now it is common to find blogs sitting within conventional websites. The blog is really a publishing engine which allows companies to put updated information on their site and out into the wider web quickly and easily.
The blog sections of the sites may be called something like latest thinking or Insights and publications”. These are used to showcase company and industry news, you’re not likely to be seeing a long list of posts on what the CEO had for breakfast!
So having a blogging function in your website will allow you to publish up to date news really easily. There are two main benefits to this. Firstly, your website visitors will be able to get a really accurate idea of who you are and what you are doing.
Secondly, and very importantly, Google loves site that publish regular, fresh content. So if you want to be found on Google, using a blogging function on your site will be a huge help.