Would you like to display a pop-up message when a user enters a value into a cell? You don’t need a macro to achieve this.
Many things that were hard or complex are now much simpler. Creating dynamic drop down lists based on previous selections used to be tricky in Excel. Dynamic arrays make it straightforward.
The most common type of Data Validation in Excel is a drop down list. In the example below I allow the user to select a year, then a month (using a drop down) and then enter a valid day in the month.
A drop down list in Excel can help speed up data input and ensure the user has entered a valid entry. If you have only a few choices, creating the drop down can be a quick process.