Computer keyboards can make two types of apostrophe marks, referred to by typographers as dumb apostrophes and smart apostrophes. Dumb apostrophes are a straight mark, the kind used to denote a foot measurement and the kind most often used when typing on a keyboard. Smart apostrophes have a clockwise curve at the bottom. Smart apostrophes are more difficult to type but generally look nicer than dumb apostrophes.
Press the button to the left of the Enter or Return button on your PC or Mac keyboard.
Hold "Alt" on a PC keyboard and type "0146" with the number pad to create a smart apostrophe. You need to activate "Num Lock" to create this apostrophe.
Press "Option," "Shift" and the right bracket button simultaneously to create a smart apostrophe on a Mac. The right bracket button is above the Return button and looks like "]".