Repeating Digits

Lily was trying to figure out the decimal equivalents of some fractions. She figured out that one third (1/3) could be calculated by doing 1 divided by 3 on her calculator.

A bunch of repeated threes can be represented like this:

Now Lily does the same for finding two thirds. She does 2 divided by 3 on her calculator and gets this:

The calculation is correct, but the answer is not complete. How do you write this? 

What does the 7 at the end mean?