The assignment operator (=) is used to create variables.  For example,

A = 10; // This is a scalar

S = "A string"; // Creates a string

S = "A string " + "by concatenating two"; // String concatenation

C = A; // Assign the value of A to C

V = [1, 2, 3]; // A vector with entries separated by commas

V = [1:2:10]; // A vector created by the range operator

M = [1, 2, 3; 4, 5, 6]; // A matrix of two rows and three columns

M = [V, 4, 5, 6]; // A vector by concatenating with another vector

M = []; // An empty matrix

A = 10; B = 20;

C = A + B; // Adds the two scalars

D = C^3; // Takes the cubic power of C

A = [10, 20]; B = [11, 21]; // Creates two vectors

C = A + B; // Adds the two vectors element by element. Works for matrices too

C = A * 2; // Multiplies each entry of A by 2

A = [1, 2, 3; 4, 5, 6]; B = [1, 2; 3, 4; 5, 6]; // Creates two matrices

C = A*B; // Multiplies the above two matrices of compatible dimensions

C = A`; // Matrix transpose

C = A.^2; // Squares each element of A

A = [1, 2; 3, 4]; B = [5, 6; 7, 8]; // Creates two square matrices

C = A.*B; // Element by element matrix multiplication

C = A.^B; // Each element of A raised to the power of corresponding B element

C = Inv(A); // Matrix inverse

C = A/B; // Matrix left division. Equivalent to A * Inv(B)

C = A\B; // Matrix right division. Equivalent to Inv(A)* B

A = [1, 2, 3, 4];

C = A(1); // The first entry of A

C = A([1:3]) // The first three entries

A = [1, 2, 3; 4, 5, 6]; // A matrix

C = A(1,1); // The entry at the first row & first column

C = A(1,:); // The first row and all columns

C = A(1,[1,2]) // The 1st and 2nd column entries in the 1st row

C = A([1,2,3]) // The first three entries in column major order