RStudio Server provides access to RStudio in a web browser, which can be particularly useful for servers or for users who prefer working in a browser. There's a free version and a professional version. The free version does not require a registration key.
If your inquiry pertains to issues with a registration key or questions about licensing, I recommend reaching out directly to RStudio's support team through their official website. They can provide the most accurate and up-to-date information. rstudio 9 registration key free
RStudio Cloud allows you to do data science in the cloud. You can sign up for a free account which includes limited compute resources. For more extensive use, there are paid plans. RStudio Server provides access to RStudio in a