I can think of each flip as a choice between two options, heads or tails. So for each flip, I have two choices, and the choices are independent of each other. Therefore, to find the total number of choices, I can multiply the number of choices for each flip. That means the total number of sequences is 2^8, which is 256. 
A coin is flipped eight times, and the sequence of heads and tails occurring is recorded. How many distinct sequences are possible?