A picture says more than a thousand words.
Images can be displayed in many ways in WordPress, from simple usages to complex galleries, to even mostly wordless PhotoBlogs. Let's look at some of the different options for PhotoBlogs and Gallery scripts.
PhotoBlogs are different from normal blogs. Normal blogs put the emphasis on the words with only the occasional image featured. PhotoBlogs are all about the images and not the words.
The easiest way to get started with photoblogging on WordPress is to either install Johannes Jarolim's YAPB (yet another photo blog) plugin.
YAPB adds all of the functionality of a standard photo blog directly to WordPress with a minimum of configuration. It includes automatic image resizing, exif data, and other tools. Johannes' site has links to themes already incorporating YAPB, otherwise you can make your own.
PhotoQ takes a slightly different approach, it gives you a queue which you can fill with photos to be posted on your photoblog. PhotoQ is geared to batch processing of photos and it features batch uploads, automatic image resizing, exif support, watermarking and automatic posting via cronjobs among other features. PhotoQ works with most WordPress themes without adaptation and includes an auto-configuration option for some of the most popular photo centric themes.
There are many PHP and Javascripts available that will allow you to create and manage online galleries on your WordPress site. Here are just a few that have been successfully integrated with WordPress. As of Version 2.5, WordPress has included a gallery function using the [gallery] shortcode.