Hindi Fonts or Devnagari fonts are those fonts which are used to type in Hindi. Hindi Fonts are of two types Legacy fonts or Unicode based Fonts. These fonts show Hindi characters in their internal coding, unlike Unicode Based fonts which shows special characters in English represent the Hindi Fonts e.g. Mangal Font.
Legacy fonts are those fonts which are being used for a very long time and it became legacy. Such as Kruti Dev, Devlys etc. These Fonts were created for Typewriters with due time it stuck. That is how Kruti Dev is came into being it worked on the principle of QWERTY keyboard to reduce tangling of keystrokes. Devlys and Kruti Dev are part of legacy fonts and others like Krishna, Chanakya etc. One Thing Common to all is that They Share the same Keyboard Layout But their Style and formation of Characters differ that's why they have a different name for their fonts.
Unicode Based Fonts works completely different in comparison to the legacy font. In legacy font, each alphabet will print unique and equivalent word pre-embedded for that language. Whereas Unicode based Fonts use bit mapping for producing glyphs, so each alphabet will be produced symbolic specimen in english. Unicode based fonts can only be used for Computers. It is easy to achieve good speed with comfortability. Mangal font is an example of Unicode based font. You can download any font after that just click install and you will be able to use that font anywhere on the system.