Suppose you have a set of numbers like: 1, 2, 2, 4, 5, 6, 6, 6, 7. The mean (which is 4.33...) tells you what the arithmetic average number of your set of numbers is. The mean is highly sensitive to "outliers." Meaning, if you have a fairly large number (and the rest of your numbers are small or vice versa, really), it greatly affects the mean. Check it: take a set of numbers like 1, 2, 3. Find its mean (the mean is 2). Then check the mean of 1, 2, 3, 94. You'll get 25. It drastically changed the value! The median tells you what number lies in the middle of your set of numbers. So in this case, the number 5 is the middle number (there are four numbers to the left and four numbers to the right). The median can be fairly deceptive when working with these types of problems because you could have 1, 3, 100 as your set of numbers, in which case 3 would be the median. Knowing that 3 is the median here doesn't tell you too much other than that it's in the middle. The mode is a bit nicer in that it's just the most common number in your set of numbers, so in this case we'd get a mode of 6. Even mode has a drawback: what if all of your numbers only show up once? Well, you didn't really learn anything new about the set of numbers. Each of these has its drawback, but sometimes you can extract information like: what is the "most likely" number to be picked out of our set of numbers? The mode. Or if I kept picking numbers, what would be their average value? The mean. Or if I lined up the numbers, what number is in the middle? The median. At first glance, the mode is the one that is most applicable, and often the utility of these three make a lot more sense when dealing with probability functions (like when dealing with what is known as the Maxwell-Boltzmann distribution ). Edited for a little clarity. More on reddit.com

Mean is the average of all your numbers, median is the middle number when they're in order, and mode is the number that appears the most. If the set of numbers is 20, 20, 50, 80, and 100, then the mean would be 54, the median would be 50, and the mode would be 20. More on reddit.com

Mean is all numbers added together then divided by how many numbers there are. Median is the number in the middle when you arrange a set of numbers from least to greatest. Mode is the number that appears most often in the set More on reddit.com

the mode is the value that appears the most often. if you graphed a distribution it would be the "peak" More on reddit.com