A spreadsheet term.
A worksheet contains a grid of 'cells'. Each cell within a worksheet has a row and column address that uniquely identifies it, for example A5, C7.
The 'active cell' is the cell that has the current focus. i.e. if you type on the keyboard, that is the cell that will hold whatever it is you are typing.
When you click into a cell on the worksheet the edges become highlighted with a bold, black line. This helps you to identify the active cell.
Challenge see if you can find out one extra fact on this topic that we haven't already told you
Click on this link: Active Cell