Denoted by *e*n, [1, 0, 0, 0...0] to the nth number. So in R3, *e*1 is [1,0,0], *e*2 is [0,1,0], **e****e**oted by *e*n, [1, 0, 0, 0...0] to the nth number. So in R3, *e*1 is [1,0,0], *e*2 is [0,1,0], **e****e**oted by *e*n, [1, 0, 0, 0...0] to the nth number. So in R3, *e*1 is [1,0,0], *e*2 is [0,1,0], *e*3 is [0,0,1]