In short, a "lemon" is a defective consumer good (not necessarily a car) that is under warranty where the manufacturer has failed to fix it within a reasonable number of repair opportunities.

Lemon law = breach of warranty law. What makes a consumer product legally a lemon is not simply that the fact that it's defective; rather, it's the fact that the manufacturer failed to repair the defect within a reasonable time period (and is now legally required to refund or replace the defective good). If the consumer good wasn't under warranty, then the manufacturer is not breaching any warranty by not fixing it.

Not at all. The law can apply to any consumer "good" where there's a warranty that gets breached. RVs, motorcycles, home appliances, boats, drones, furniture, etc. are all examples of consumer products that could qualify under the lemon law.

It's a form of breach of contract. Lemon law applies to almost anything with an express warranty or guarantee that you purchased. The warranty is a promise to repair a product if it becomes defective during the warranty period. A breach occurs when a manufacturer fails to promptly reimburse a consumer after it fails to repair a defective good after a reasonable number of attempts.

Lemon law claims generally consist of two main warranty breaches: breach of express warranty and breach of implied warranty. "Express" warranties mean the warranties or promises (ideally written and thus easy to prove) that the manufacturers included with the vehicle or product. For instance, most new cars come with a 3-year/36,000 bumper-to-bumper limited warranty. And many additionally include other warranties, such as a 5-year/60,000 powertrain warranty covering defective powertrain components. These are classic examples of express warranties.

Absolutely not. It's only a guarantee that the manufacturer will make all necessary repairs when problems occur. If the defects are covered by a warranty, most typically a dealership, on the manufacturer's behalf, will make the repairs. They get a reasonable number of attempts, or reasonable period of time, to fix the defects. When they fail, the good should be branded a "lemon." At that point, you can legally demand for your money back or a replacement. When manufacturers fail to honor this simple principle, legal action becomes necessary.

In addition to express warranties, consumer goods come with implied warranties--most commonly the implied warranty that the goods are merchantable. Although related to breach of express warranty claims, a claim for implied breach of warranty (of merchantability) is separate. Both claims fall under the lemon law, but breach of implied warranty works a little differently. One significant difference is that it is not required to prove the manufacturer had multiple repair opportunities. Let's say, for example, that your brand new car spontaneously combusted into flames and was destroyed. Thus, no repair attempts occurred. Does that mean you don't have a lemon law claim? Of course not; that would be ridiculous. Here, you'd have a very strong lemon law case under a breach of implied warranty theory.

Despite being called a warranty, in reality, extended warranties are merely contracts with the dealership. They are not part of the express warranties given by the manufacturer. Thus, if a dealership fails to work on your car, for instance, when you bring it in under the extended warranty coverage, then you may have a basic breach of contract claim against the dealership. But, you won't have a lemon law claim against the manufacturer based solely on an extended warranty sold separately by the dealer.

In general, you sue the manufacturer in lemon law claims, not the store or dealer that sold the defective good. That's not to say you can't sue the dealer or store.