Globale linker
Book 1
- Chapter 1
- Chapter 2
- Chapter 3
- Chapter 4
- Chapter 5
- Chapter 6
- Chapter 7
- Chapter 8
- Chapter 9
- Chapter 10
- Chapter 11
- Chapter 12
- Chapter 13
- Chapter 14
- Chapter 15
- Chapter 16/17
- Chapter 18/19
- Chapter 20
- Chapter 21
- Chapter 22/23
Book 2
Book 2 Ch. 5 Cookies
Cookies are small text files that have a variety of uses. They are used by the operating system and applications to remember user states. Cookies are sent from the server to the user's browser in the HTTP response header. The browser accepts the response from the page assigning the cookie, then accepts (or gives the user the chance to accept or reject) the cookie. The browser program then stores the cookie information in a file on the user's system.
When the HTTP request is generated, any cookies on the user's system with a path and domain name matching the current HTTP request will be passed along in the request header. The server can then test for and evaluate the contents of the incoming cookie.
- A server can pass no more than 20 cookies to a user's computer.
- A user can store no more than 300 cookies total.
- Cookies store name-value pairs as text strings.
- Cookies can expire as soon as the user exits his or her browser.
- Cookies can be set to expire on a future date.
A cookie header appears to your browser as follows:
set-cookie: name=value; expires=date; path=path;
domain=domain; secure
The name-value pair is the only information required to generate a cookie. All other cookie attributes are optional.
One of the most common uses of cookies is to store information about the user to maintain state.
- Cookies cannot read files from your hard drive
- Cookies cannot contain viruses
- Once set, cookies are sent from your system (one-way) to the server. The server does not access your computer to read the cookies. After a server sends you a cookie, it has no knowledge that you have the cookie until you request another page from that server.
- Cookies can only respond to the server that sent them.
- Cookies cannot gather your passwords and distribute them
- Cookies are stored in a unique place as a text file, and are not executable
- Cookies can keep track of the sites you have browsed
- Cookies can store personal information. However, they only store information that you provided to the server that wrote the cookie.
- Cookies are not encrypted
- Cookies can be used to target you for marketing and banner advertisements.
Browsersettings can be adjusted to accept or reject cookies, or to alert the user every time a cookie is sent.
Navigator stores cookies in the cookies.txt file. This file lists all the cookies downloaded by the browser. Selecting and deleting the contents of this file will remove the cookies from your system.
IE stores cookies under a subdirectory of Windows called Cookies. IE stores each cookie as a separate text file. These files can be deleted.
