What is the difference between a code block and a separate function in programming?

A code block is a sequence of instructions grouped together, for example, inside curly braces or indentation, which are executed sequentially. It does not have a name of its own and cannot be called separately.

A separate function is a named block of code that can be called from different parts of a program, pass parameters, and receive results. Functions help structure code, make it reusable, and facilitate testing.

Example in Python:

# Code block
if x > 0:
    print("Positive number")
    y = x * 2

# Function

def double(number):
    return number * 2

result = double(x)
print(result)