Number of stages for a software, before it is released, may vary project to project and company to company. But in general pre-alpha (nightly builds, which may not have all features implemented), alpha (with all requirements implemented, unit-tested but before testing by QA), beta (after Alpha-testing by QA with known issues and possibility of hidden defects) and stable (after Beta-testing by a small team from customer-side or by general public) are common stages (which are publicly declared).
Within the company, between beta and stability versions, there may be multiple steps.
Beta version will go to Release Candidate version, which means it is in better state than beta (after defects found on beta version are fixed) and is the potential release. Apple computers labels this stage as Golden Master. This stage means there are no known bugs which will prevent the software from meeting its purpose.
Finally, Release Candidate becomes Gold or Stable release which is handed over to the actual users. It just contains the fixes for last minute issues found on Release Candidate (if any).