Final answer:
Integer data types store exact numbers and can be signed or unsigned. They vary in size, which is determined by the number of bytes they use.
Step-by-step explanation:
Integer data types are designed to hold exact numbers, which can be understood as numbers obtained by counting objects or from definitions that have infinitely many significant figures. These types of data can be either signed, allowing for representation of negative values, or unsigned, which are exclusively non-negative. Integer data types come in different sizes represented by the amount of bytes of memory they consume; common sizes are 1 byte, 2 bytes, 4 bytes, and 8 bytes, which define the range of values the integer can store.