Alignment of large language models and machine learning is about shaping its behaviors to support the values of its maintainers and discourage behaviors that go against the same values.
Like, you can't get a positive response by asking it to write a phishing letter for you, and it will refuse to divulge information it might know which is considered personally identifiable information.
Unfortunately, the alignment applied since ChatGPTs launch has reduced its efficacy in other ways. While it behaves better, it may be less helpful or less accurate in the older models like 3, and 3.5 with respect to their debut.