
The context window is the amount of text an AI model "sees" and remembers within a single conversation: your question, the chat history, uploaded files, and the model's reply. Think of it like working memory or a notepad on your desk - once a note falls off it, the model simply doesn't know about it anymore. Window size determines whether an entire contract, a month of customer correspondence, or a whole codebase fits into one conversation - and how much that will cost your business. Below is a plain-language look at what a context window is, how it's measured in tokens, and why it matters to developers and business owners alike when choosing an AI tool.





