Google Sites is Google's website builder. When you compare Google Sites to WordPress or another advanced website builder, it won't really compare, as it has far fewer features. However, you still have what you need to create a blog, portfolio, business site, or business intranet. It's also simple enough for non-professional users to create websites for their families, friends and classrooms.
If you're planning to use your Google site for professional purposes, a custom domain will further polish it. It wouldn't be Google if it didn't integrate well with other Google applications and, of course, Google Sites allows you to add content from other Google tools through the Insert menu. Google Sites doesn't have widgets outside of the Google Apps options, but you can add any external option with an embed code. Zapier's picks for the best free website builders include some feature-packed options if the simplicity of Google Sites isn't what you're looking for.