Author Template Tag Help Needed

Hey all. I’m new here so sorry if this is an obvious question. I searched but there’s too much info for this tiny problem I have.

Without any prior knowledge of php or css, I was able to figure out how to customize the default template in WP 2.7. I noticed that a “posted by” author tag is not in this particular template. Can someone tell me the tag to list the author of each post?

Thanks in advance.