The sum of $\frac{2}{3} + \frac{1}{3}$ is:

$\frac{2}{3} + \frac{1}{3} = \frac{2 + 1}{3} = \frac{3}{3} = 1$

Final Answer:

$\boxed{1}$

Would you like more details or have any questions?
Here are 5 related questions to expand your understanding:

1. What is $\frac{2}{3} - \frac{1}{3}$?
2. How do you add fractions with different denominators?
3. What is $\frac{5}{6} + \frac{1}{6}$?
4. Can improper fractions be converted to mixed numbers?
5. What is the sum of $\frac{2}{5} + \frac{3}{5}$?

Tip: When adding fractions, ensure their denominators are the same, then add the numerators directly.