eigenvector values

I'm sure this will be a very easy question for someone to answer: I
entered the formula to get eigenvectors and eigenvalues for a matrix.
Some of the entries in the eigenvector have this format: -0.1407 +
0.0125i, and the next column will have an entry -0.1407 - 0.0125i.
What does the i stand for?

Thank you.

matlab user:
<SNIP ... oh well ...
> What does the i stand for? (in constructs like a+bi)

a hint:

help i
% followed by
sqrt(-1)

us

The results are just complex.

Regards,
Stefan