Arrays are much like lists but they are confined to one type of data. The example linked needs parentheses around the print statements, but you can see below some of the differences between lists and arrays: import array a = array.array( "B" , range ( 16 )) # unsigned char b = array.array( "h" , range ( 16 )) # signed short print (a) print ( repr (a.tostring())) print (b) print ( repr (b.tostring())) /Users/mattfassnacht/PycharmProjects/untitled6/venv/bin/python /Users/mattfassnacht/PycharmProjects/untitled6/functions.py array('B', [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]) b'\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f' array('h', [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]) b'\x00\x00\x01\x00\x02\x00\x03\x00\x04\x00\x05\x00\x06\x00\x07\x00\x08\x00\t\x00\n\x00\x0b\x00\x0c\x00\r\x00\x0e\x00\x0f\x00' Process finished with exit code 0 http://effbot.org/librarybook/array.htm