Language models are computer programs made to estimate the likelihood of a piece of text. "Hello, how are you?" is likely. "Hello, fnarg horses" is unlikely.
Language models can answer questions by estimating the likelihood of possible question-and-answer pairs, selecting the most likely question-and-answer pair. "Q: How are You? A: Very well, thank you" is a likely question-and-answer pair. "Q: How are You? A: Correct horse battery staple" is an unlikely question-and-answer pair.
The language models most relevant to AI safety are language models based on "deep learning". Deep-learning-based language models can be "trained" to understand language better, by exposing them to text written by humans. There is a lot of human-written text on the internet, providing loads of training material....