ALGOL, the root of all modern language was introduced around 1960s. It gave the concept of structured programming to Computer Science Society. ALGOL was popularized by computer scientist like Corrado Bohm, Guispee Jacopini and Edsger Dijkstra.
You can get a clear idea about basic structure of loop from this video. It will be helpful for you. Feel free to make comments about this video.
Take a look. Its about looping
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