The developer tab allows you to write macros, run macros that you previously recorded, or create applications to use with Microsoft Office programs. It is a relatively advanced tab which you would likely benefit from reading up on before using.
See the Excel help file for further information (click the help icon and search for "developer tab").
active tab
in the home tab
Home Tab
It is on the Page Layout tab.
the Home Tab
Sheet tab
Home tab
At the bottom of the screen.
If you save it when the first tab is open, then it will reopen on the first tab.
On the Insert tab.
Right-click on the tab and select option for tab color.
This would be under the tools tab. Go into excel and click on this tab to see all of the options that are available for modifying your axis labels.