What it means
A breach of contract occurs when a party does not perform one or more of their obligations under a binding agreement — for example, by failing to deliver goods, not paying on time, or doing work to a substandard quality. Depending on how serious the breach is, the other party may be entitled to claim compensation (damages), and in some cases to terminate the contract. Not every minor failure justifies ending the contract; the seriousness of the term breached matters.
How it's used
When the builder abandoned the job halfway through, the homeowner sued for breach of contract to recover the cost of finishing the work.