In past, we only have one thing and that was Website with some HTML pages. You have to hire someone to create it as it was technically difficult to develop.
Where as today, we have blogs which are easy to create and develop and you do not need a professional web developer to develop a blog for you. Blogs are more flexible and easy to update.
Blogs are more active than a website, people update blog regularly as they create it to tell others about the stuff they love where as a website is a “Develop and Forget” thing as they put all information at once about their brand and product until they have new brand or product to introduce.
Websites are static and revolve around certain and limited stuff. You might have visited some sites where they always have limited number of pages mostly Home,Services, Pricing and Plan, About and Contact page where as blogs are dynamic their main page always have fresh stuff,called Posts mostly ordered by date that is the reason you see new post at top and older at bottom or on other pages.
Blogs are informative, people create them to write about some topic like a cause, subject or anything. They are created to increase reader’s knowledge but websites are made to create a brand awareness.
So if you want to write personally for something you can create a blog and there are many platforms to create a free blog easily like WordPress.com and Blogger.com and if you are sole proprietor or comapny, you should go for a website and do not forget to create a professional email address before making a blog.
And best choice is “Website with a Blog” yes you read it right. Self hosted WordPress platform made it easy to create a blog and website at the same time and now these days everybody has it.