factors go into these numbers evenly. Lets start with 6 and try some numbers

1 goes into 6 6 times

2 goes into 6 3 times

3 goes into 6 2 times

4 does not go into 6

5 does not go into 6

6 goes into 6 1 time

So the factors are 1,2,3 and 6

let's try 8 the same way

1 goes into 8 8 times

2 goes into 8 4 times

3 does not go into 8

4 goes into 8 2 times

5 does not go into 8

6 does not go into 8

7 does not go into 8

8 goes into 8 1 time

so the factors are 1,2,4 and 8