Key Concepts

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Sessions Definition

A session is a storage strategy that consists of information server-side. A session id, as well as other session variables, are stored client-side in cookies or localStorage and allows the browser to make an HTTP request to get the persistent session information from the server.

Sessions are terminated when a user exits the browser or after client storage is cleared.

Sessions & Cookies vs. localStorage
Lesson 1 of 2
  1. 1
    How do web applications keep a user logged in? How does a shopping site remember what’s in your cart? And how is this done securely? In this lesson, we’ll define what a web session is, what cookie…
  2. 2
    HTTP(S) protocol on its own is stateless, meaning requests and responses are just relaying information back and forth with no knowledge of a specific user. But web developers want to create engagi…
  3. 3
    It’s a bit clunky for the client to remember to tack the session ID onto every request. Because of this, the session ID is often kept client-side in the form of session cookies. Cookies are tiny …
  4. 4
    Cookies often store sensitive information, especially when they’re used in session management. Cookies are also used to store a user’s personal preferences or history, which should also stay secure…
  5. 5
    Reading cookie data can involve some tedious syntax and relying on cookies to be attached for each HTTP request can affect a website’s performance. Cookies are also quite limited in storage. Cookie…
  6. 6
    As you can see, the localStorage syntax is very straightforward and makes storage and retrieval easy. So why hasn’t everything transitioned to using localStorage or sessionStorage? What are the pro…
  7. 7
    Users and web developers should be concerned with session hijacking, an attack in which an attacker steals session identifiers an…
  8. 8
    Session management is an important aspect of web design and implementation. In this article, we’ve discussed how cookies, localStorage, and sessionStorage can facilitate session management. We also…

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