Alpha testing is the initial phase of validating whether a new product will perform as expected. Alpha tests are carried out early in the development process by internal staff and are followed by beta tests, in which a sampling of the intended audience actually tries the product.
Products typically go through several stages of trial prior to their release to a mainstream audience. The alpha test phase is closely associated with proof of concept (POC) efforts. Using the first two letters of the Greek alphabet to differentiate internal testing from customer-facing testing originated with software development, but the labels are now used by product engineers in many industries.
In software development, the concept of alpha and beta testing is often associated with classic Waterfall design models, in which one development phase must be completed before the next one can begin. In DevOps and iterative approaches to software development, such as continuous integration (CI) and continuous delivery (CD), the formal alpha/beta concepts do not apply. Instead, every CI/CD iteration is an alpha test, and in effect, alpha testing never ends.