Working on Fourier Transforms

 I've been working on Fourier Transforms. This involves integrating the product of the function of my choice with exp(-iwt) for all times that are real numbers. So I chose to try a unit step function between -T and T. And it worked. I got the standard answer.

Then I set up a spreadsheet to produce a graph of the answer.

It's an odd shape. It what's the unit step looks like recast as a function of frequency. I'm still working on the significance of it. What does it actually mean?