Post (Detailed step by step instruction, used as a reference post in the video) : blog.sudobits.com Setup Ruby On Rails, on Ubuntu 12.04 (Precise Pangolin) LTS in one simple command, Using the Rails Installer Script. Just Drag the script to terminal and relax, installation will be completed within few minutes (Depending on your internet speed). If something went wrong and you got stuck in middle, then follow the above link(post) for installing things one by one, or you can explain the problem via comment. Download Rails Installer Script from Github – github.com Thank You checkout my Rails App: bootstrapthemes.me (a marketplace for bootstrap themes)
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How to Install "Ruby On Rails" on Ubuntu 12.04 (Using Rails Installer Script)