Works on Advaita Vedānta usually commence with the description of the anunbandha-catuṣṭaya. Anubandha is that which connects or binds, the factors which bind the entire system together into a connected whole. There are four such factors and hence the word ‘catuṣṭaya’ (a group of four).
The first anubandha is ‘adhikārin,’ the person competent to study and practise the science. The second is ‘viṣaya,’ the subject matter dealt with in the treatise. The third is ‘prayojana,’ utility to be gained by its study and practice. The last is ‘sambandha’ or connection, usually between the book that purports to deal with the science and the science itself, or, between the work and the utility promised.
Though this is used as a ‘technical word’ in Advaita literature, it is a general concept that can be applied to other fields of knowledge also.