CI/CD is a process that automates the build, test, and deployment stages of software development to reduce errors and increase efficiency. It involves continuous integration, which builds and tests software on a regular basis, and continuous deployment, which automatically deploys code changes to production when certain conditions are met. CI/CD can improve the reliability of software by removing human error and increasing trust in the code, allowing for faster release cycles and more frequent bug fixes. However, it also requires an initial investment of time and resources, and may not be suitable for all projects or teams, particularly those with large changes to their codebase. Additionally, CI/CD is not a substitute for having good tests, but rather complements them by ensuring that tests are run automatically and gatekeeping code changes.