90秒で分かるRuby on RailsとかのWebフレームワークって何なの?

Webアプリケーションの開発になくてはならないWebフレームワーク。Ruby on Railsなどのフレームワークって一体どういうものなんでしょう?90秒で学んでみましょう!
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Understand difference between RGB and CMYK in 90 sec Understand difference between RGB and CMYK in 90 sec
Learn about the chirping of a cricket (Korogi) in 90 seconds Learn about the chirping of a cricket (Korogi) in 90 seconds
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