The sum of $1 + 1$ is:

$1 + 1 = 2$

Would you like more details or have any questions?

Here are five related questions to explore:

1. What is $2 + 2$?
2. What is the sum of $1 + 2 + 3$?
3. How do you perform addition with negative numbers?
4. What is the sum of $1.5 + 1.5$?
5. How is addition used in algebra?

Tip: When adding two numbers, the order in which you add them doesn't matter—this property is called commutativity.