Built in function - str_repeat

I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs! I love dogs!

User defined function - String concatenation

I am 20 years old
4020

How do functions work?

PHP functions are blocks of code that can take in variables/values (although they don't have to), perform statements, and return a value. Functions are reusable, and they make it so that the user doesn't have to manually repeat statements everytime they want to perform a task. The function does it for them.