As indicated in a previous lesson, each comparator operation has a drop down menu where you can select between different data types.
Now what are these used for? It's very simple. Every variable or constant that you use in your PLC program has a specific data type. When you're going to compare these variables or constants using comparator operations, you need to define the exact data type for the instructions as well. This means that you need to tell the instruction what the data type of the variable or the constant is that you wish to compare. In this and the next lessons, you're going to learn how to do that.