is it a blog?

When is a blog not a blog? One of the joys of blogging, it seems to me, is the blogroll and the comments. Without these, blogging is a solitary activity, a mere webpage. With them, it is a social activity, one which enables conversation, almost in the manner of a sharing circle. A friend has created an online diary, but it is not really a blog, as it doesn't have any facility to add comments. Nor does it have a blogroll or an index of posts (which is awkward if you wanted to read bits selectively, or link to individual posts). Also I do think that brevity is the soul of wit. (This doesn't necessarily imply short blog posts, but it does imply saying what you have to say succinctly, and editing yourself.)