HTTP Header
The line Content-type:text/html\r\n\r\n is part of HTTP header which is sent to the browser to understand the content. All the HTTP header will be in the following form −
HTTP Field Name − Field Content
For Example
Content-type − text/html\r\n\r\n
There are few other important HTTP headers, which we will use frequently in our CGI Programming.
| Sr.No. | Header | Description |
| 1 | Content-type: | A MIME string defining the format of the file being returned. Example is Content-type:text/html |
| 2 | Expires: Date | The date the information becomes invalid. It is used by the browser to decide when a page needs to be refreshed. A valid date string is in the format 01 Jan 1998 12:00:00 GMT. |
| 3 | Location: URL | The URL that is returned instead of the URL requested. You can use this field to redirect a request to any file. |
| 4 | Last-modified: Date | The date of last modification of the resource. |
| 5 | Content-length: N | The length, in bytes, of the data being returned. The browser uses this value to report the estimated download time for a file. |
| 6 | Set-Cookie: String | Set the cookie passed through the string |