There are some common operations on matrices. The operators which are applied term by term, implying that the matrices should be of similar size, sometimes are termed to as array operations. These involve addition and subtraction.
The Matrix addition means adding the two matrices term by term, that means they should be of the similar size. In mathematical terms, this is written cij = aij + bij.
Similar to the matrix addition, matrix subtraction means to subtract term by term, therefore in mathematical terms cij = aij - bij. This would also be accomplished by using a nested for loop in many languages, or by using the - operator in a MATLAB.
The Scalar multiplication means to multiply each and every element by a scalar number
This would also be accomplished by using a nested for loop in many languages, or by using the * operator in a MATLAB.