Short Definition
Inference is the process of running a trained model on new inputs to produce outputs.
Intuition
Training teaches the model. Inference uses the trained model in an application.
Technical Definition
Inference executes the learned model function with fixed parameters, often under latency, throughput, cost, and reliability constraints.
Example
A production API performs inference when it returns a fraud score for a transaction.
Common Misunderstandings
Inference is not training.
Inference quality depends on preprocessing, prompts, retrieval, and system design, not only model weights.