The "Blog Archive" gadget is used, by some blog owners, to provide a date sequenced post index . Some blog owners, with smaller blogs, would like their readers to index their blogs by post title - but without the date being involved. They would like a straight alphabetically ordered list of post titles. Blogger does not have a "Title Index" gadget. It's not hard to make one, however, for smaller blogs.
What Blogger won't tell you