Data recovery from corrupt external hard drive. sir i have an external hard drive of SEAGATE 80

Question

sir i have an external hard drive of SEAGATE 80 GB that is to be connected via USB . it is now corrupted may be because it was removed off directly and not by using saely remove option. now when connected it is seen in my computer but when i click on it it says that disc is not accesible as it is corrupt . iwant to recover it's data please help me