Contrastive Analysis (CA Lado 1957) is a course offered to Master 1 students of Language Studies (LS). It deals with the various theories of language acquisition and language teaching. It also includes Error Analysis (Corder 1960's), then Interlanguage (Selinker 1972? Corder 1972, then Second Language Acquisition (SLA, Krashen 1981) to end up with BICS and CALP (Cummins 1979).