This is the first question we all ask ourselves when starting a blog: Blogger or Wordpress?. As you are probably ready to start your new blog already, I will get right into answering it.
Assuming that you are new to blogging, you probably would rather use a free service over a paid one (at least for the time being). Wordpress.com and Blogger are probably your two best options. The key difference between the two, and probably the ultimate reason why you decide on either one or other, is the customization. Wordpress.com comes with many beautiful templates that fit all styles of blogs, while Blogger has very few templates. This being said, Wordpress.com does not allow HTML customization (or ads that you put in), while Blogger does allow both HTML customization and your own ads.
So for your first blog, if you are more interested in having a very nice-looking blog, I would go with Wordpress.com, but if you think you may be interested in having ads in your blog, your best bet is Blogger.
Both of the websites links are below so feel free to check these sites out and good luck with your blog!