Here is my comment on the blog Tackling Accessibility on The Web by @Treehouse.
An OK article, but a few of the techniques are incorrect/outdated. The data table caption is for a *title*, not a description. Never use tabindex (except 0 and -1 for keyboard focus with JavaScript interaction). Title attributes on links (and in general) is no longer recommended; screen readers usually don’t read them, browsers don’t support them for keyboard users, and it’s not supported (hardly) on mobile. Most implementations just have redundant information anyway. Also note that ARIA landmark roles are a good place to start learning ARIA, but there is much, much more to learn.
Another comment also states that the title attribute on links is not a great practice and provides a couple great links. Also note that the title attribute is still a must for an iFrame to describe its content.