If you want to create macros, record macro & write macro or want to create some application, so you need to activate Developer Tab. It helps you to record & write macros & it displays your recorded macros.
Here is the process : -
click on Office Button then click Excel Options.
Then select from the left category options Select Popular then click on Show Developer tab in the Ribbon & Ok.
This process will activate your developer tab, now you can write or record your macros.