In a statistical series of data point, the number that is the most frequently repeated expresses the mode:
54, 55, 58, 58, 58, 75, 76,78 ( the mode is 58, it has the highest frequency)
Now assuming we have a series like, 54,55,58,58,58,75,76,76,76,78:
We have here 2 numbers that occurred 3 times each, that is 58 (3 times) and 76 (3 times), we say that this set of data is bimodal, because it has 2 modes, 58 and 76. HOPE THIS IS HELPFUL