The concept I will remember most 5 years from now is definitely classical conditioning. This video explains classical conditioning:
This article gives several real world examples of classical conditioning, but the one I'm going to remember most is how it's used in advertising. As someone who is going into retail and the apparel industry, I find advertising for clothing to be very interesting. It seems like the most popular way to advertise clothing is to advertise it with sex. Advertising the product with sex works because sex elicits a good feeling, and so sex would be the unconditioned stimulus and feeling good would be the unconditioned response. Pairing sex with apparel would cause the apparel to become a conditioned stimulus and feeling good to be a conditioned response.
I'm going to remember classical conditioning 5 years from now because at that time I'll be making decisions about how to advertise my own apparel. Right now I don't believe using classical conditioning to advertise is very ethical, because the product isn't selling itself and consumers are almost being tricked into purchasing some things. This idea has been reinforced in my Retail Merchandising course, though it's never been explained in terms of classical conditioning. Classical conditioning in advertising is huge in the industry I'm planning on working in, but no matter what happens in the future, I'll still encounter it everyday while seeing and hearing advertisements all around me.