and software industry. Statistical Quality Control (SQC) and Operations Research (OR) units Since mid-forties, ISI pioneered in research and application of Statistical Quality Control (SQC) in India. Walter A. Shewhart, the statistician known as the father of SQC, and other experts of this field visited ISI over the years. The first Statistical Quality Control and Operations Research (SQC & OR) unit of ISI was set up in Mumbai in 1953, followed by Bangalore and Kolkata units in 1954. In 1976, this unit was transformed into the SQC & OR Division, which now operates seven units, located at various industrial centres in IndiaKolkata, Delhi, Bangalore, Chennai, Pune, Mumbai and Vadodara. These units partake in technical consultancy with public and private organisations, in addition with performing research and training activities. The branch at Giridih was set up in 1931 and it has two operational units, viz. the Sociological Research Unit and the Agricultural Research Unit. Achievements Over the years, researchers of ISI made fundamental contributions in various fields of Statistics such as Design of Experiments, Sample Survey, Multivariate statistics and Computer Science. Mahalanobis introduced the measure Mahalanobis distance which is used in multivariate statistics and other related fields. Raj Chandra Bose, who is known for his contributions in coding theory, worked on Design of Experiments during his tenure at ISI, and was one of the three mathematicians, who disproved Euler's conjecture on orthogonal Latin squares. Anil Kumar Bhattacharya is credited with introduction of the measures Bhattacharyya distance and Bhattacharya coefficient. Samarendra Nath Roy is known for his pioneering contributions in multivariate statistics. Among colleagues of Mahalanobis, other notable contributors were K. R. Nair in Design of experiments, Jitendra Mohan Sengupta in Sample Survey, Ajit Dasgupta in Demography and Ramkrishna Mukherjea in Quantitative Sociology. C. R. Rao's contributions during his association with ISI include two theorems of Statistical Inference known as Cramér–Rao inequality and Rao-Blackwell Theorem, and introduction of orthogonal arrays in Design of Experiments. Anil Kumar Gain is known for his contributions to the Pearson product-moment correlation coefficient with his colleague Sir Ronald Fisher at the University of Cambridge. In 1953, India's first indigenous computer was designed by Samarendra Kumar Mitra who headed the Computing Machines and Electronics Laboratory at ISI Calcutta. The Indian Statistical Institute was also hosted the first two digital computers in South Asia; the HEC-2M from England in 1956, and the URAL from the Soviet Union in 1959.