No matter the uppercase or lowercase letters in the URL of the website, as long as the URL format is unified, there is only one URL address for the entire site corresponding to this page (there is only one URL address included by the search engine), there is no scattered page weight, which is not conducive to search engines Ranking issues. The URL case that has been continuously enlarged and emphasized by the webmaster forums of major stations before, disperses the weight of the website because many webmasters mistakenly believe that the uppercase and lowercase URLs are the same URL address, resulting in a website with multiple corresponding sizes. Writing different URL addresses is included by search engines, resulting in poor page rankings due to scattered page weights. For example: \"http://www.abc.com /A.html\" and \"http://www.abc.com/a.html\". Because the user's custom input method is lowercase, generally new websites will suggest all lowercase letters in the URL. However, it is generally not recommended to adjust the URL address of an old station that has been online and has a stable ranking and inclusion. Because there is no way to transfer the page weight to the new URL by performing a 301 jump on the old URL, you will face problems such as the inclusion of new sites and the re-accumulation of weight of the new URL, and there will be a loss of website traffic.