How Does the ChatGPT Web Application Retain Context Information to Achieve Infinite Conversations?

I have recently been exploring the capabilities of the GPT-3.5 Turbo API, and I came across an intriguing question regarding the maximum token limit of 4096. It seems that in order to implement multi-turn conversations, one needs to include previous dialogue in the prompt.

However, I noticed that the ChatGPT web application allows for seemingly infinite conversational turns while retaining context information. How is this achieved?