Inference

Fundamentals

The moment an already-trained AI model is actually used - answering your question or generating your image.

AI has two phases. Training is the slow, expensive part where the model learns from data. Inference is the everyday part - the trained model receiving your input and producing an output in seconds.Every ChatGPT reply, every AI-generated image, and every voice transcription is an act of inference. Companies pay for inference by usage, which is why AI services often bill per request or per token.