HTTP

Question 1

What is a client?

Answer 1

service requestor

Requests content or service from a server.
Clients initiate communication sessions

Question 2

What is a server?

Answer 2

the provider of a resource or service

Runs one or more server programs, which share their resources with clients.
await incoming requests

Question 3

Which HTTP method does a browser issue to a web server when you visit a URL?

Answer 3

GET

Question 4

What three things are on the start-line of an HTTP request message?

Answer 4

1. An HTTP method, a verb (like GET, PUT or POST) or a noun (like HEAD or OPTIONS), that describes the action to be performed.
2. The request target, usually a URL, or the absolute path of the protocol, port, and domain are usually characterized by the request context. The format of this request target varies between different HTTP methods.
3. The HTTP version, which defines the structure of the remaining message, acting as an indicator of the expected version to use for the response.

Question 5

What three things are on the start-line of an HTTP response message?

Answer 5

1. The protocol version, usually HTTP/1.1.
2. A status code, indicating success or failure of the request. Common status codes are 200, 404, or 302
3. A status text. A brief, purely informational, textual description of the status code to help a human understand the HTTP message.

A typical status line looks like: HTTP/1.1 404 Not Found.

Question 6

What are HTTP headers?

Answer 6

Meta data of request; like meta data of html file

HTTP headers let the client and the server pass additional information with an HTTP request or response. An HTTP header consists of its case-insensitive name followed by a colon (:), then by its value. Whitespace before the value is ignored.

Question 7

Where would you go if you wanted to learn more about a specific HTTP Header?

Answer 7

MDN

Question 8

Is a body required for a valid HTTP request or response message?

Answer 8

Not all requests have one: requests fetching resources, like GET, HEAD, DELETE, or OPTIONS, usually don’t need one.

Not all responses have one: responses with a status code that sufficiently answers the request without the need for corresponding payload (like 201 Created or 204 No Content) usually don’t.