Your mother needs some items from the grocery store. You could easily remember a few items, correct? But what if there are 10 or 15 items with different quantities to be bought? To avoid confusion, you make a list. It has all the items written in order. You can arrange the list as per items. For example, the first few items are groceries, next comes vegetables, then dairy, and finally some confectionaries, yum!
Lists are simple and effective tools that help you organize information in order. We use lists in our daily life. Whether in form of a shopping list or timetable. Computers also use lists to arrange the information. Sometimes such lists are also called arrays. The list can be 1D, 2D, or 3D(d stands for dimensional.
One dimensional

Two dimensional

Mark that any other combination would make it a different list. 1,2,3,4 is not the same as 2,3,1,4. Lists can also be 3D but for sake of simplicity, we will constrain ourselves to 1-D lists for now.
Now we will learn about lists at blockly. We request you follow along for better learning.