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@reulbg
Take a coin. Flip it. There are two outcomes, either heads or tails. Each is equally likely to land face up. So of the 2 outcomes, you call something, you have a 1 in 2 chance of that occurring. Flip it again, the outcome is independent of previous flips so you still have a 1 in 2 chance of getting it right. If you were to flip a coin 100 times, it'll be 50 heads 50 tails, give or take a few.
But should you wonder what is the probability of calling it right twice in a row, both flips you have a 1 in 2 chance of getting the right answer, but getting both the first AND the second correct is 1 in 4. Because both flips are 1 in 2, multiplied together gives 1 in 4. This can carry on, making the probability of 100 heads in a row, not impossible, but highly improbable.
All more complex probability stuff stems from that really. So a dice each outcome has an equal chance of 1 in 6. But say you have a dice where two of the faces were 5s and no 6s, the probability of rolling a 5 is 2 in 6, or simplified to 1 in 3, which makes it more probable to occur. etc etc etc.