Inmotionghosting has a great historical timeline showing images of the front and backend of WordPress starting with 1.0 up to version 3.8. Through these images, you can see the natural progression of features, designs, and layouts WordPress has gone through during the past 10 years.
For many within the WordPress community, a post like this triggers nostalgic memories of the first version of WordPress they used. For me, it was WordPress 2.2. Shortly after I started using WordPress, 2.3 was released which introduced the ability to add tags to posts. WordPress 2.3 also added update notifications so that users would know when a new version of WordPress or plugins were available. Which version of WordPress did you start with?