How do the functions like rand and Math.random work? How were they made?

Answer 1

They are library functions created by mostly third party programmers of such languages.
This might sound funny but they are actually built upon real mathematical equations, for instance I do know of someone who once created his own random library making use of the time library, he did it by creating a function which uses the time in seconds at that particular moment to generate a random number I.e
class Random1:

def random_no_generator(u):
t = list(str(u))
y = t[(len(t))-1]
return(round((y * 300)/450))

@classmethod
def integer(cls):
import time
l = time.time()
return(random _no_generator(l)

Note:
This should be packaged into a Random1.py script.

So if you imported Random1 class's script and used the Random1 class method it was going to generate a random whole integer for you.
I.e
import Random1
y = Random1.integer()
print(y)
# outputs = random integer
I hope I made sense to you though
Note this code was written in python.

Answer 2

random numbers generated using these such modules are actually pseudo-random numbers or false random numbers! They aren't actually random, as they work on with some definite parameters and do an out-tracking random operations and display the final output as a randomly generated number!

Answer 3

I think random is based on computer/server internal clock to return a random number.