1.cookie
- Storage period: valid forever, unless manually deleted;
- Data size: generally around 5-10MB;
- Scope: can be accessed in all pages under the same domain name;
- Purpose: Long-term storage of data on the client side, suitable for data that needs to be saved across multiple sessions.
2.sessionStorage
- Storage period: Persistently valid until the end of the current session, invalid when the browser is closed;
- Data size: generally around 5-10MB;
- Scope: limited to the current window or tab;
- Purpose: Temporary storage of data on the client side, suitable for temporary data that needs to be saved in a single session.
3.localStorage
- Storage period: valid forever, unless manually deleted;
- Data size: generally around 5-10MB;
- Scope: can be accessed in all pages under the same domain name;
- Purpose: Long-term storage of data on the client side, suitable for data that needs to be saved across multiple sessions.
- The type of saved value is restricted, the browser cannot read it in private mode, and cannot be crawled;
4.indexedDB
- browser built-in database
- Transaction: IndexedDB uses transactions to ensure data consistency and integrity.
- Object Store: IndexedDB uses an object storage mechanism to store and retrieve data.
- Index (Index): An index in IndexedDB is composed of one or more attributes, and each attribute can be selected to be unique or non-unique.
- Asynchronous operation (Asynchronous): In order to avoid blocking other parts of the application, IndexedDB uses asynchronous operations for all data reading and writing.