Step 1: The greatest integer function, \( \lfloor x \rfloor \), takes the value of the greatest integer less than or equal to \( x \).
The integral is split into two parts:
\[
\int_{-1}^{0} (x - \lfloor x \rfloor) dx + \int_{0}^{1} (x - \lfloor x \rfloor) dx.
\]
Step 2: After evaluating, we find the result of the integral is 0.
Final Answer:
\[
\boxed{0}
\]