Some, but not all, fractions are integers. Fractions that can be simplified so that they have a 1 as the denominator are integers. Fractions that cannot be expressed this way are not integers.
The fraction 4/1 has a denominator of 1 and is thus an integer. It equals the integer 4. The fraction 10/2 is also an integer because it can be simplified to 5/1. This fraction also has a denominator of 1 and equals the integer 5.
On the other hand, 4/6 is not an integer. Its reduced form is 2/3, which has a denominator of 3.
The set of integers is comprised of the counting numbers (1, 2, 3, ...), as well as 0 and the negatives of the counting numbers.