What are those HTTP Response Codes??
Tags: http, webdev, web, beginners
Published: 2023-09-29 18:29:03

Whenever we visit a website and for some reason, it gets failed to load, we get the response codes such as 'error 403 - Forbidden' or 'error 404-Content Not Found', ever wondered what those codes represent?

## HTTP Response Status Codes

HTTP response status code represents whether the specific HTTP request has been successfully completed or not. Those codes are grouped under 5 categories:

1. [1xx - Informational](#1-informational-100-to-199)
    
2. [2xx - Successful](#2-successful-200-to-299)
    
3. [3xx - Redirection](#3-redirection-300-to-399)
    
4. [4xx - Client Error](#4-client-error-400-to-499)
    
5. [5xx - Server Error](#5-server-error-500-to-599)
    

### 1\. Informational (100 to 199)

These codes indicate that the request has been received and that the process is continuing.

* **100 - Continue:** This response is used to let the client know that the request has been received and has not yet been rejected by the server.
    
* **103 - Processing:** This is used to indicate that the server has accepted the complete request, but has not yet completed it.
    

### 2\. Successful (200 to 299)

These codes indicate that the request was successful and that the requested information has been sent in the response.

* **200 - OK**: The request was successful, and the requested information has been sent in the response (the desired result).
    
* **204 - No Content:** The request was successful, but there is no content (data information) to send in the response.
    

### 3\. Redirection (300 to 399)

These codes indicate that the client must take additional action to complete the request.

* **301 - Moved Permanently**: The requested resource has been permanently moved to a new URL. This generally happens when a website changes its URL, hence, the request cannot reach the desired servers.
    
* **302 - Found**: The requested resource has been temporarily moved to a new URL. The client should use the new URL in this and future requests.
    

### 4\. Client Error (400 to 499)

These codes indicate that there was an error with the request made from the client side.

* **400 - Bad Request**: The request was either invalid or cannot be fulfilled for the instance.
    
* **401 - Unauthorized**: The client must authenticate itself to get the requested response.
    
* **402 - Payment Required:** This code is reserved for future use.
    
* **403 - Forbidden**: The client does not have permission to access the requested resource.
    
* **404 - Not Found**: The requested resource could not be found on the server.
    
* **405 - (Method Not Allowed)**: Requested HTTP method is not permitted for the specific resource.

* **409 - (Conflict)**: There is a conflict with the current state of the resource. It is often related to issues like resource locking or simultaneous updates by multiple clients.

### 5\. Server Error (500 to 599)

These codes indicate that there was an error with the server while processing the request.

* **500 - Internal Server Error:** An unexpected condition was encountered by the server and no specific message is suitable.
    
* **503 - Service Unavailable:** The server is currently unable to handle the request due to a temporary overload or maintenance.
    

## Conclusion:

HTTP response codes are an important part of the HTTP protocol, as they provide a way for servers to communicate information about the status of a request to clients. Understanding these codes can help us troubleshoot issues with your website or application.