A blog post is an individual web page on your website that dives into a particular sub-topic of your blog.
For instance, let's say you start a fashion blog on your retail website. One blog post might be titled, "The Best Fall Shoes for 2019". The post ties back to your overall blog topic as a whole (fashion), but it also addresses a very particular sub-topic (fall shoes).
Blog posts allow you to rank on search engines for a variety of keywords. In the above example, your blog post could enable your business to rank on Google for "fall shoes". When someone searches for fall shoes and comes across your blog post, they have access to the rest of your company's website. They might click "Products" after they read your post, and take a look at the clothing items your company sells.
A blog post links back to your overall blog site. For instance, right now, you're on blog.hubspot.com/marketing/what-is-a-blog. The "what-is-a-blog" section of the URL is tied back to /marketing/, which is the blog as a whole.
A blog is typically a section of your business's website -- but, unlike the rest of your website, you need to update the blog section frequently by adding new posts. Additionally, your blog is a tool that allows you to engage more with an audience, either by analyzing how many readers share your blog posts on social, or by allowing readers to comment on your individual posts. In this way, a blog is more like a two-way conversation than the rest of your website. However, a blog can also be an entire website, and often is, if the blog is for personal use alone -- for instance, a travel blog.
A lifestyle blog is a digital compilation of an author's personal interests, daily activities, or opinions on a subject. A lifestyle blog typically covers multiple hobbies or talents of the writer, rather than focusing on one subject alone. For instance, a lifestyle blog might include a section for fashion, health and wellness, travel, and relationships. A lifestyle blog is often highly personalized, so it can often feel like you're reading a friend's curated journal entries.
There are plenty of benefits to blogging -- it helps drive traffic to your website, it enables you to better convert that traffic into leads, it allows your business to establish authority in an industry, and it continues to help your business grow and attract new customers months and even years after publication.
To learn more about the benefits of blogging, check out Why Blog? The Benefits of Blogging for Business and Marketing.
A wiki is a collaborative space where anyone who visits the site can edit, share, or publish content -- Wikipedia is one of the most popular examples of this. On the other hand, there is typically only one person, or a team of people, with admin permissions to edit, share, or publish to a blog. Website visitors who come across the blog can potentially leave comments at the bottom of the blog post, but they cannot publish to the site or edit the posted material.