The Difference Between Posts and Pages
Unless you are already very familiar with WordPress, you might not be sure whether to present your content as a post or a page. The rule of thumb that is generally quoted is that pages are for more or less permanent content while posts gets constantly updated. For example, your About and your Contact information are placed in pages, while your newest ideas and discoveries will be posts.
Things might get more complicated however. What if you have a slider on your home page that pulls in posts from a certain category. Pages don't have categories, so the page explaining your services for example, can't be pulled into the slider. Or you created a category for descriptions of your various services and placed that category in your menu only to realize that all your services are described in pages that can't be placed in categories. You thought you did the right thing since services are permanent content but you end up having to redo everything.
So, here is a summary of the basic differences:
Posts have categories and tags while pages don't. This means that only posts can be displayed and called in by category. Posts can also appear in an archive by date of creation, while pages cannot.
Posts can have different formats. You will probably use the standard post format for your average post but you could also publish a single sentence as a status update, an aside or a quote, to name just a few formats.
WordPress automatically creates excerpts for your posts. These are used to create listings of your posts and each excerpt links to the full article.
Since posts are meant for content that is ever changing, WordPress saves all your revisions. If you publish something and then change your mind and want to go back to an earlier version, you can do so with a couple of simple clicks.
Pages don't have excerpts associated with them nor do they have various formats, or saved revisions. They can be displayed with different templates, however. Depending on the template you choose they could have one, two or no sidebars, they could have different styling and/or different widgeted areas. It all depends on the templates that come with your theme.
Pages are hierarchical while posts are not. A top level page can have subordinate pages which can have further subordinate pages. This makes organizing pages in your dashboard easier and is also reflected in the main menu WordPress creates automatically.
If you are creating a website that adheres closely to the traditional blog format you don't have to worry too much about the difference between posts and pages. If you create a website where you want to highlight more permanent content, it pays off to carefully think about which content should go into pages and what should be your pasts. It will make sure that your site is well organized and you will save time and hassles in the long run.