ligatures are when you join two or more glyphs into a single one. For instance, instead of having the two characters = and > to form => if you had ligature support you would see ⇒. Some terminals have support to recognize sequences like => (and others obviously) and turn them into their corresponding ligatures (only for display though, the actual file contents remain umchanged)
127.0.0.1 is localhost (i.e. your own computer) so either the nerd is incompetent or he just outed himself for the crime