You absolutely can use photos in a regular blog, and many of the most popular blog hosting services provide easy-to-use image upload tools. However, simply including photos in your blog does not a photo blog make. Photo blogs have distinct characteristics in that they are primarily a collection of photos organized chronologically and include some form of commentary by the photographer. If the blogging photo or photos you are using are your personal photos, you should be fine. However, there may be issues of copyright infringement if you use photos from other sources such as online news sources. To learn more about copyright issues and photo blogs, read up on Fair Use issues.