Hi, Arrays and lists both are used to store data in Python, but they don't serve exactly the same purposes. The main difference between a list and an array is the functions that you can perform to them. It does take an extra step to use arrays because they have to be declared while lists don't because they are part of Python's syntax, so lists are generally used more often between the two, which works fine most of the time.
So, python lists are very flexible and can hold completely heterogeneous, arbitrary data, and they can be appended to very efficiently, in amortized constant time. If you need to shrink and grow your array time-efficiently and without hassle, you can simply use lists. But they use a lot more space than arrays. While the array, on the other hand, can hold only homogeneous data, all of the same type, and so it uses only sizeof(one object) * length bytes of memory.
For example, you can divide an array of numbers by 3, and each number in the array will be divided by 3 and the result will be printed if you request it. If you try to divide a list by 3, Python will tell you that it can't be done, and an error will be thrown.