[Purpose/significance] This study attempts to demonstrate LIS’s distinctiveness as compared with other information-related disciplines from the perspective of information processing.[Method/process]It does so primarily through logical deduction complemented by cases-based induction. The logical deduction starts from the concept of information, which defines information as the combined product of data and meaning. [Result/conclusion]It shows that an information processing can take either data or meaning as input and output, giving rise to four information-processing orientations: data to data, data to meaning, meaning to data, and meaning to meaning. It then shows that LIS processes both data and meaning in its professional work and research; and that it accepts any data and meaning as input, but produces primarily data that facilitate information search/access and meaning that concerns LIS objects and LIS domain itself.