Pros:
Carrd.co offers a "one page" drag and drop website builder, although with a little know-how, extra pages can be created fairly easily. If you're moderately comfortable with technology, it's reasonably straightforward to build a simple, no-frills website. With the free plan you pay nothing at all, your domain name ends in .carrd.co and there's a discreet Carrd credit.
Or, for $19 a year (current pricing) you can remove the Carrd branding and use your own domain name. I think this is amazing value for getting started with an online presence, especially if you only need a simple website.
Cons:
I think Carrd is best in class for what it offers, however, you should know the websites available are *simple* and won't suit everyone's needs. Don't expect a blog, dropdown menus, or multiple nested pages. Also, although I find it (fairly) easy to use, I've worked with others who have not found the interface completely intuitive.
Ideal Customer:
You have a little comfort with technology, you need a *simple* website, and you're on a tight budget.