Alternatively referred to as a caret, a cursor or text cursor is a blinking horizontal or vertical line ( ) that indicates where new text starts when you begin to type. For example, below is an empty text box, clicking in this box gives you a text cursor to indicate you can start typing.
If your text cursor is a block or rectangle instead of an I-beam, press the Insert key.
Text cursor example
As you start to type, the text cursor stays at the end of the line to indicate the insertion point. Pressing the left arrow key moves the cursor to the left and lets you insert text at the text cursor's position. If there was text after the cursor pressing the right arrow key moves the cursor to the right.
Also, when working with text that's more than one line you can press the up arrow key to move the text cursor up or down to move down one or more lines.