Step 1: Introduction of the Act
The National Rural Employment Guarantee Act (NREGA) was passed in the year 2005. It aimed to provide employment opportunities to rural households and enhance livelihood security.
Step 2: Implementation
It came into force in February 2006 in 200 districts in the first phase, and later extended across the country.
Step 3: Name change
In 2009, the act was renamed as the Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA).
Step 4: Conclusion
Thus, the National Rural Employment Guarantee Act came into force in:
\[
\boxed{2005}
\]