> For the complete documentation index, see [llms.txt](https://bharat-tiwari.gitbook.io/our-tech-journal/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bharat-tiwari.gitbook.io/our-tech-journal/javascript/localstorage-and-sessionstorage.md).

# localStorage and SessionStorage

When it comes to store or persist data on the client side, the only option available before HTML5 was cookies.

While cookie is a good option to store data on the client side, it has a limited capacity of only 4kb. Also, issue with cookies is they get sent to server with every request thus adding extra load to each request. Since anyone can add a cookie to the browser, its not very secured, a cookie added manually or by some ill-intended automation code may actually appear to be to be coming from a valid user session to the server.

With HtML5, there are two new options to store data on the client side - `localStorage` and `sessionStorage`

| StorageType        | Size Limit |                        Expiration Period |                   Readable on |
| ------------------ | :--------: | ---------------------------------------: | ----------------------------: |
| **Cookies**        |     4KB    | set by the code when creating the cookie |                    any window |
| **LocalStorage**   |    10MB    |            Never (until user clears out) |                    any window |
| **SessionStorage** |     5MB    |                             On Tab close | only the tab where its ceated |