Built-in Functions vs. User-defined Functions

1. Built-in Functions:

   • Examples: print(), len(), max()
   • Challenges: These functions are ready to use, but they don't always fit our needs. Sometimes, using them can be frustrating because they can be too strict with what they do.

2. User-defined Functions:

   • Here’s an example of a function that finds the factorial of a number:

   def factorial(n):
       if n == 0 or n == 1:
           return 1
       else:
           return n * factorial(n-1)
   

   • Challenges: Making your own functions can be tricky. You need to understand how functions work, what they return, and how to handle things like loops and calls within themselves. This can be tough for newbies.

3. Solution: Start small! Try simple examples first. Once you get the hang of it, you can move on to harder problems. Also, using comments and guides can make learning easier.