One, HTTP status code:
1XX: (Information status code), the accepted request is being processed.
2XX: (Success status code), request normal processing completed.
3xx: (redirect status code), additional action is required to complete the request.
4XX: (Client Error status code), the server cannot process the request.
5XX: (Service side error status code), server processing request error.
Two, explain the difference between 301 and 302 Jump:
301: Permanent redirection. Indicates that the requested resource has been assigned a new URI, and the search engine will replace it with a new URI.
302: Temporary redirect. Indicates that you want this request to be accessed using a new URI.
303:303 and 302 are similar, but 303 explicitly indicates that the client should take a get to get the resource.
301 and 302 will SEO have different effects on search engine optimization. such as a jump to the B site. 301 Optimization b Site, 302 optimization a site.
In detail, both the 301 and 302 status codes represent redirects, meaning that the browser automatically jumps to a new URL address when it gets the status code returned by the server.
This address can be obtained from the location header of the response (the effect that the user sees is that the address a that he entered becomes another address B)-that's what they have in common.
The difference between them is. 301 indicates that the resource of the old address A has been permanently removed (the resource is inaccessible), the search engine crawls the new content, but also exchanges the old URL to redirect the URL;
302 indicates that the resource for the old address A is still (still accessible), and this redirect only temporarily jumps from the old address A to address B, and the search engine crawls the new content and saves the old URL.
Review HTTP status Codes +301 and 302