It is a border.
You could call it highlighting but more commonly you would call it selecting.
The active cell is where things will go when you start to type something into a spreadsheet.
The Active Cell on a spreadsheet is the cell where the cursor is pointing. That means that you can write to or erase the contents that cell location directly. A spreadsheet program has the entire array in memory, but the Active Cell is the place where it is 'looking or thinking about' at any particular moment.
It is the active cell.
In a spreadsheet application, it is the cell that has focus and that input can be made. The cell with the bold boundary is the active cell.
An active worksheet is a spreadsheet that is visible in a workbook. When you open a new workbook, the first sheet you see is the active worksheet.
Active Cell or Insert Location
Active cell
Yes, the selected cell and the active cell typically refer to the same thing in spreadsheet applications like Excel. The active cell is the currently highlighted cell where data can be entered or edited, while the selected cell indicates the cell currently in focus. In most contexts, these terms are used interchangeably to describe the cell that is being worked on at that moment.
An active sheet is the worksheet you currently are accessing.
LED lights
A workbook is typically in edit mode when the cursor is active in a cell, allowing you to input or modify data. Additionally, if the formula bar is showing the content of the selected cell, this also indicates edit mode. In many spreadsheet applications, the presence of an "Edit" option in the toolbar or a blinking cursor within a cell can further confirm that the workbook is in edit mode.