The gray system font is a protected font and cannot be deleted casually. The blue A is a font file! Available fonts, (I think all fonts are available, don't load what you see,) Korean and other fonts are prepared by the system, which is convenient for you to browse Korean and other fonts in your computer. More than 400 m is not big! Of course, you can also delete some. Be extra careful when deleting them. Otherwise, some font files may be garbled! If it is win7 system, you can download an IT House Rubik's Cube 3.0, which has font cleaning! Automatically filter out fonts that can be deleted, which is convenient for you to delete.