Here we will learn what is the meaning of all the status code that come under the 1xx series (i.e. indicating informational message in different situations).

HTTP 1xx series status code are as an acknowledgement to the client. With the help of HTTP 1xx series status code a web server responds that the received request is under processing by the server.

HTTP 1xx series status code is classified only in three different types mentioned as below:

1-) HTTP 100 – Continue

If serever sends a code “100 – Continue” it indicates that the part of the request has been received and the client can continue to send the remaining request.

Generally first client sends a request header along with a statement “Expect: 100-continue” and in response, receives the 100 code from the server side to proceed by sending the request body.

2-) HTTP 101 – Switching Protocols

If the client request asks server to switch the communication protocol and in response server accepts it, then code “100 – Switching Protocol” is received as an acknowledgement send by the server.

3-) HTTP 102 – Processing

If WebDAV (World Wide Web Distributed Authoring and Versioning) request is sent along with multiple sub-requests including complex requirements, the server may need considerable time for processing the request hence the server sends the status code “102 – Processing”. Purpose of this status code is to avoid timeout errors at client side, in order to inform the client that the server has received the request and is processing it.