Capitalization Normalization is the process of ensuring that search engines, websites and users always see URLs that force each letter off the URL to display as lower-case. This is a way to standardize the URLs on a site, so that they are not displayed and shared in formats that you would not like, but also, so that non-standard versions of a URL are understood and processed, but re-written in the address bar to be all lowercase. Servers and search engines actually understand one URL that is all lower-case to be different than one that includes capitals, so in theory, the different URL could include different content. To keep things simple for Google, always displaying and linking to the lower-case version of the URL ensures that Google crawlers will not come across many instances of non-standard URLs. This means less 301 redirecting, and easier migrations, if URLs ever need to change in the future. It can also help consolidate link profiles, if Google has links indexed to both versions of the URL. Most of this happens automatically for Google, at least over time, but providing Google an efficient and clear experience when crawling is always the best strategy, rather than hoping that Google can figure it out on their own.