1In one sentence
Memory lets ChatGPT keep facts about you between chats, and custom instructions let you set standing rules for how it should answer, so every new chat starts a little informed.
2New words
- Memory — a small notebook where ChatGPT stores details about you (your job, your preferences, projects you mentioned). Found under Settings, then Personalization, then Memory.
- Saved memories — facts you asked it to remember, or that it judged useful. You can read and delete each one.
- Reference chat history — a switch that lets ChatGPT look back at your past chats for relevant details, beyond the saved list. Turn it off and it stops doing so; the help pages say how long old details take to clear.
- Custom instructions — a form where you write who you are and how you like answers (tone, length, language). It is applied to every chat.
3Why you would want it
Telling ChatGPT "short answers, I am a bakery owner, use metric units" in every chat gets old. Set it once and the answers fit you from the first message. Memory also means you can say "like last time" and be understood.
4Try it now
- Click your name, then Settings, then Personalization.
- Open Custom instructions. In the "how to respond" box, type: Keep answers short. Use simple words. Use metric units. Save.
- In a new chat, type: Remember that I run a small bakery called Sam's Bakery and I open at 7 a.m.
- Open another new chat and ask: What time do I open?
5What you will see
A "Memory updated" note under your message in step 3, and in step 4 the right answer without you repeating it. Under Settings, Memory, you can see a summary of what it holds and delete any item.
6Watch out
- Memory is on by default. If several people share your account, or you discuss private matters, review the list or switch it off. Chapter 1.17 covers temporary chats, which can read memory but never add to it.
- Memory is small and selective, and the size depends on your plan. It is not a recording of everything; important facts belong in a Project file.
7Go further
Ask ChatGPT: What do you remember about me? and correct anything wrong. Then read Chapter 1.13 for ready-made helpers built by other people.