Glycolysis literally means a glucose molecule is hydrolysed (broken down) by water into two. I bet you’re itching to find out what it’s broken down into. Glad you asked. It’s broken down into these molecules called pyruvate.
It didn’t even to go far, and we’ve already got a net of 2 ATP molecules produced! Another by-product of this reaction is NADH (reduced NAD – the addition of a proton/H atom/electron constitutes a reduction, whereas the loss of either species constitutes an oxidation) of which 2 are obtained.