The sum of $1 + 1$ is $2$.

Would you like more details or have any other questions?

Here are some related questions to expand on this:

1. What is the result of $2 + 2$?
2. How do you add two larger numbers, such as $123 + 456$?
3. Can you explain how addition works in base-10 (decimal) arithmetic?
4. What is the difference between addition and multiplication?
5. How does addition change when using negative numbers, like $1 + (-1)$?

Tip: When adding two numbers, remember that you are simply combining their values to find a total sum.