Blogging is a great way to open up and share your views, opinions and experiences with the world.
You can blog about anything - there are literally no limits, and as I'll discuss there are several perks and benefits to writing a regular blog.
The best bloggers are absolutely passionate about blogging.
In fact, the reason that they blog and write posts are as much to aid them as it is to aid the readers.
Oftentimes documenting your progress (by writing an online diary or journal) can be extremely beneficial because it lets you get all of the information out of your head (since you're writing it down) so that you can focus on what really matters and how you're going to move forward.
Also, it lets you get a perspective view of what you've done and what worked and what didn't, meaning future decisions are now more easy to make (and you'll be more successful making them).
Lastly, blogging is a great way to motivate yourself.
If you set yourself a series of new years' resolutions (as many bloggers do) or a list of targets to accomplish for the year and publish them for the year, you are announcing to the world your goals.
This can create amazing leverage within yourself, since you know that people are more likely to ask if you've taken action on working towards your goals or not.
While it is very difficult to make a full-time income from blogging (unless you're getting thousands and thousands of people visiting your blog every single day), there is always the potential to earn a few extra dollars a day by putting banner ads and Google AdSense blocks on your page.
This should never be the main goal, but it's a nice bonus.