Caveat Emptor: Let the buyer beware. Although widely tossed about as being the "American" way and although buyers should indeed be aware, buyers should be more wary of sellers than products. What buyers should be especially aware of is how to track down the seller and manufacturer and to deal only with those you can indeed hunt down. If you can hunt them down, you may indeed be able to hold them responsible in one fashion or another. When we lived in a relatively simple society with relatively simple services and products that the average person could adequately evaluate, caveat emptor was the general rule but there have always been exceptions for those services and products beyond the ken of the average consumer and there has always been a distaste for taking advantage of the less than average consumer.
Caveat Venditor: Let the seller beware. The UK is ahead of the US in moving toward caveat venditor and away from caveat emptor and it is a direct result of the growing complexities within which we live. It is more appropriate to put the responsibility on the person or company that has the greater knowledge, not to mention the imbalance of power between sellers and buyers ever shifting toward the sellers. Indeed, much of that shift comes from the necessity of dealing with sellers who are at a distance and who hide from consumers.
Merchantable Quality:"goods must reasonably conform to an ordinary buyer's expectations, i.e., they are what they say they are" Required in many jurisdictions, still difficult to enforce. IMO, the violations of this warranty are rampant and increasing. It got going with cheap items and we didn't hold manufacturers/sellers to account for the product, let alone the loss of our time or other damages from these products and now it is spreading like wildfire.
Warranty of Fitness: "is implied when a buyer relies upon the seller to select the goods to fit a specific request" ASK QUESTIONS and get the answers, pin down the seller. And save packaging, print promo materials you used to make your decision. We are all increasingly at the mercy of sellers who have specialized knowledge upon which we MUST rely. Do not let them weasel in their responses. Especially keep this in mind when dealing with professional service providers who also sell products. Whether the seller to you (the professional service provider) is responsible or not is a separate issue from whether or not the product meets the warranty and much of the providers information is from the manufacturer and not within your ability to easily obtain. Make that provider cough it up.
Strict Liability: An elegant and simple concept. One is responsible for one's actions or failure to act. It applies in many areas, especially the actions and omissions of professional service providers. The reason the actual article on this topic is so short is because the concept itself is so very broad and pervasive. Stict liability is most often enforced through the criminal laws and a variety of tort actions. Take the time to scroll down the page and look at the links on the right hand side.
Concealed defects: Sellers are not permitted to hide defects. Usually, the defect is "latent" meaning it can't be readily determined by a buyer upon examination. Beware of any representations by sellers followed by sold "as is". They may well suspect there's a latent defect so you should too. I would also say it could be applied to professionals. Isn't a private sanction from a licensing board a hidden defect in their license?
Puffery: This is the gray area between a truth and a lie in advertising. "Our product is the best." Best for whom? Best based on what criteria? Puffing is what sellers do to avoid answering those persnickity questions that would lead to them be liable under the above concepts. Learn to recognize it. Listen and read carefully. Is it a promo or a fact?
Negligence: It boils down to the question of reasonableness of the average person or A SPECIFIC SET STANDARD. Professionals have an incentive to keep the standards down to prevent being negligent. The public must force the standards upward.
Fraud: "intentional deception made for personal gain or to damage another individual", often both IMO. Yes, the definition of fraud is just that simple. I will have much to say about fraudfeasors in this blog as fraud is rampant and always has been.
Privity of Contract: Must say that Wikipedia is growing increasingly better. Law is ever evolving although it often lags behind the realities of life. Nonetheless, creative lawyers will challenge law that should evolve and change and they can find alternatives. No contract? Try a tort action.
Privity of Duty: Historically, one had to be in privity of contract for someone to owe another a duty of care but that is less so now.
Duty of Care: Sets a minimal standard but it isn't as minimal as most sellers and providers would have you believe.
Tort: You've been wronged or hurt and there's no contract involved or the contract is irrelevant (for legal purposes). Grossly oversimiplified but it's really a term that means little to anyone who isn't a lawyer but is very useful when doing research to find cases that aren't contract related.
Common Law: In law, it has a history. However, I think they're taking too narrow a view of the concept. Common law is what all of us as a society use to determine our interactions and the courts are involved on the close calls, to split hairs or hold the stubborn and recalcitrant to account. In history, there is also a clear distinction made between law and equity. That distinction is still important as some things can only be resolved with money damages (law) and some with a directive to do or prohibit (equity) but, in the US, most courts have the ability to do either or both. Money is often an inadequate relief but it is also often the only relief a court can give.
Malfeasance, misfeasance, nonfeasance: OK, I don't like wikepedia on this one so I'll be back to work on those.
Ken: knowledge and understanding. To us Scots, it has a broader meaning of knowledge, understanding, perception of people and products, of legal and social obligations.