The Language Proficiency Test (LPT) checks that IBPS Clerk candidates know the official language of the state or UT they applied for.
It is usually a reading, writing and speaking test in that local language.
Candidates who studied the local language in 10th or 12th standard are normally exempted.
LPT is qualifying in nature — it does not affect your merit ranking.
Candidates who fail the LPT are not considered for allotment in that state.