1.'On' button makes the calculator's buttons clickable and get live to the display.
2.'Off' button turns off the calculator and make all the buttons unclickable except 'on' button.
3.'Del' button deletes the input one by one.
4.'Clr' button clears the display.
5.To use trigonometry calculation you must use parenthesis and a degree or radian sign like this "sin(30°)"
6.You can also convert degree to radian or radian to degree by just clicking deg or rad button.
7.To work with the button n√X ,you need to input like this n√X(n,x) where n is the power and x is the digit you want to transform.
8.The %mod button indicates the remainder function of division.
9.The only % button works like a percentage.
10.The π indicates the value of Math.Pi you know.