"Free fonts" websites that repackage the system font without proper licensing. While the Windows version is free for personal use, redistributing it is a violation of EULA.
The Harrington font family is classified as a typeface, but calling it a traditional serif would be a disservice to its quirky nature. It sits comfortably in the category of "decorative" or "display" serifs. Here is a breakdown of the design elements that give Harrington its signature look: harrington font family