Recently a blog reader asked two questions as he started his own new blog:
1. Do you think I should stick to just one topic? i.e. Digital Forensics?
2. Do you think blogging is a good way to learn more about a topic of interest or should you only blog about a topic you already know a lot about?
I addressed some of these issues in my post Why Blog?, but I'll add the following.
I recommend writing about a handful of topics, but stick to topics within a certain theme. For example, my blog covers "digital security and the practices of network security monitoring, incident response, and forensics." Although I love martial arts and ice hockey, I don't write about that here. I also do not address politics, family, religion, or any other non-technical issues in this forum. I believe blog readers prefer me to stay on my listed subjects; they can visit other sites for non-technical information.
I believe it is ok to write about subjects that are outside your core expertise, but you need to warn the reader that you are a beginner. Do not presume to be an authority on a subject that is new to you. Tell the reader and let him or her be the judge. If you don't know a lot about a topic, but you want to solicit assistance, say that in your post.
If you make a habit of discussing topics that are foreign to you, you will probably not be respected, however. I don't think many readers want to visit a blog that is constantly asking how to accomplish a task. Most readers want to learn something or see a new viewpoint, not be asked questions all the time.
Richard Bejtlich is teaching new classes in DC and Europe in 2009. Register by 1 Jan and 1 Feb, respectively, for the best rates.