Quality is the most sought after word in software development. Development of any software goes through a process (sequence of steps). Quality is the umbrella that covers this entire process.
Software Engineers following a quality process and use Quality methodologies in all their tasks. Documentation and record keeping are an integral part of Software Development life cycle that define quality.
Quality processes generally aim to generate software that is bug free and conforms to the stated requirements. In all the steps of a SDLC quality checks are exercised. Processes are documented and the Engineers trained in them.
The software at the end of each development cycle is tested for conformance to the quality standards. Test Cases are built according to the requirements and executed on the software. The failed cases are analyzed and resolved by the developers. The software may then again go for another cycle of testing.