Basically a chain of url when they have more than one redirect between the initial URL and the destination URL.
In general understanding
When URL A is redirected to URL B, then after sometime URL B is redirected to URL C.
Also a combination of HTTPS vs. HTTP, www vs. non-www and trailing slash vs. non-trailing slash redirects results in site-wide redirect issues. Commonly done during website migrations or relaunches where redirects are built in series instead of in parallel.
Problem with redirect chain is they’ll Cause Crawling Issues, Hurt Website Loading Speed, you will loose Backlink Equity (Link Juice).
By using screaming frog we can identify the redirect chains present in our site.
Then click on Report > Redirect Chain
You will get a report like this,
Where you can find which URL’s have redirect chains.
2.Fixing Redirect Chains:
Just eliminate the redirects between Page A and Page B. Then 301 redirect Page A to Page C. The end result is that both Page A and Page B will be 301 redirecting the final page (Page C).