The word "blog" is short for "web log". It's meant to be a notebook, a place to write daily or weekly. Originally often made by individuals on platforms like blogger.com, for innocent non-profit self-expression. People are now turning to podcasts, videos, and social media feeds for self expression.
The simple naive blog has now evolved into an ambitious business model. Most blog articles now are made for profit as part of larger websites who employ many writers and publish many articles at regular intervals. A big site with many categories can still be considered a blog.
Monetization
A big for-profit company blog has many more options for monetization than the personal web log.
- At first glance, it seems that any blog can make some money by show advertisements. That was never true for small personal blogs, and as of 2010+ has stopped being true for even large blogs. Ad revenues have plummeted recently, as millions of websites added ads to all their pages creating way more demand than supply. It has radically affected news websites which were for a while looking like just large complex blog with tons of content. Now, nobody is making money by showing ads on blogs.
- Affiliate marketing can be a great way to monetize your traffic, but only works for some. The visitor has to actually purchase something after clicking the link. Some websites cater to an audience that is more likely or less likely to buy stuff. This is used on more sites than most people realize.
- The most common business model for blogs nowadays is to run it as a purely non-profit educational or entertainment resource, but to link each page back to the for-profit main product of the company. When you click a Google/Bing search result, and land on a nice article, click on the top left logo of the website. It will often take you to a for-profit business website, not to the blog. Many companies run a blog on the side, so visitors from search engines will land on a blog article, then find their way to the product page. At the bottom of most blog articles you will usually find a big advertisement or a mention of the website's for-profit product.