Fellow reefers can follow your progress and learn from you making the hobby easier to understand. They can even addcomments or give advice in the form of a comment.There's nothing worse than having problems and not being able to find answers.
I find it really useful, i cant be bothered creating a diary, you can bet i would misplace it any way. With blogger just type in your blog web address and there it is in front of you.
You can link to your favourite websites, forums and blogs, so everything is readily available in front of you whilst surfing the Internet.
With your blogger account there are loads of tools to help get you started and blogging could not be easier because it uses a what you see is what you get editor (WYSIWYG) so that the not so experienced surfers can do it.
Just do a search on google and get some ideas, there are plenty online.