 Cls = Clear screen
 sqrt = Square root
 root = root
 nlog = Natural logarithm
 clog = Common logarithm
 tan = Tangent
 atan = Arc tangent
 x^2 = Square
 x^y = Power
 e^x = Natural antilogarithm
 10^x = Common antilogarithm
 cos = Cosine
 acos = Arc cosine

 +/ = Change sign
 1/x = Divided by
 x! = Factorial
 PI = PI
 asin = Arc sine
 sin = Sine
 ppm = Part per million
 MS = Memory store
 % = Percent
 MR = Memory recall
 E = Exponent
 Rad = Radians
 Deg = Degrees
