What is another word for identity matrix?
Pronunciation: [a͡ɪdˈɛntɪti mˈe͡ɪtɹɪks] (IPA) 
The identity matrix, also known as the unit matrix or the elementary matrix, is a square matrix with ones on the diagonal and zeros elsewhere. It is denoted by the symbol I. Synonyms for the identity matrix include the unity matrix, the multiplicative identity matrix, and the one matrix. It is also sometimes referred to as a scalar matrix, as it behaves like a scalar in matrix operations. The identity matrix has several important properties, such as being a neutral element in matrix multiplication and being the inverse of itself. It is used extensively in fields such as linear algebra, physics, and computer science.
