Competitive inhibition: Where an inhibitor, which has a similar molecular shape to the enzyme's substrate, competes with substrate to fit to the enzymes active site
…. In the end all substrate can be broken down because the competitive inhibitors are not permanently bonded to the enzymes active site. If there is a higher concentration of substrate the amount of time it will take for all the substrate to be broken down will be less than if there is a higher concentration of inhibitor. Non-competitive inhibition: Where the inhibitor attaches itself to the enzyme at a site which is NOT the active site. This causes the enzymes shape to be changed slightly which would mean that the substrate is unable to fit to the active site. Non-competitive inhibitors do no compete with the substrate for the active site, hence their name. Non-competitive inhibitors may be permanent or not. Because the inhibitor and substrate are not competing for the same site an incrase in substrate concentration does not decrease the inhibitors effect. (MORE) 
