We normally use the Ribbed bars in the RCC work .
This article gives information on the history of these bars .
Quite interesting article.
Answer by A Quora admin:
In the US, this was an antiquated form of reinforcing that predates modern rebar. The mechanical interlock between steel and concrete is critical in reinforced concrete. Early concrete reinforcing was sometimes smooth and square. This shape did not create much friction to make a solid interlock. One solution to this problem was to twist the bar like a corkscrew with creates many teeth for a strong mechanical lock. The primary drawback to doing this is that the twisting causes the steel to work harden and become more brittle.
Here is a patent image for a twisted steel reinforcing bar, from 1884.