Glyph Master is a NPC found in Velika that sells Glyphs and adjust them. Visiting Glyph Master was previously necessary to adjust glyphs character has.
Since TERA: Fate of Arun glyphs can be changed directly from menu and visiting Glyph Master is unnecessary. Also while leveling glyphs are unlocked automatically. When nearing level cap upgraded level 58 and level 60 glyphs are dropped in dungeons. See Master Glyphs for additional info.