i love how some people just swamp in with questions like what's your niche, can you help me please, thanks for sharing like friggin bees
I'm so sick of the 'I made $x.xx on 1 click' threads. Get over it, keep it to yourself, and then share it with everybody when you start getting $x.xx for every single click. A one off click with such a high value is probably just some really fandom occurence because of some web publishing typing the value in wrong. Think yourself lucky, and stop starting these stupid threads.
It is virtually not possible to maintain the site if the topic is not known to you. If "share trade" is the niche you know by heart, then good luck and all the best to you; just do not forget to keep updating your site - google kicks out dormant sites out of index.
Niche is your market or topic. if you had a site about red bikes your niche would be red bikes and so forth. the main niche would be bikes but your micro niche is red bikes.