Some previous tests of SEO plugins, made me quite disappointed. However, they allowed me to explore the different methods used. These methods are simple and can easily be developed into a theme, for example.
This article is part of a series of three posts: the first (this one) will address the title and the robots meta tag, the second will speak about the description field and the last will be focused on keywords field.
Develop your own SEO functions with WordPress: the title