Where did Google get the idea of an Index?

[Condobloke]

Monks, a polymath and an invention made by two people at the same time. It's all in the history of the index​

In the 13th century, a monk and a polymath came up with a way to find information. Google still uses it

The need for this 800-year-old invention was so strong that two people came up with it at the same time. It's as useful today as ever.

www.abc.net.au

Eight centuries ago, the need for a way to collect and organise the contents of a book was so great that two people, in two different cities, came up with a solution – at the same time.

The index, that thing tucked inconspicuously at the end of a book was – and still is – essential, says Dennis Duncan, a writer, translator and English lecturer at University College London.

If you use Google, you're one of many in this "age of search" who have a "reliance on a certain type of index", he tells ABC RN's Late Night Live.

"It is the index that underpins the search engine … we're constantly relying on indexes."

 

[Matt.m]

That was an interesting article and i believe most internet users didn't know such things. Although many users that are familiar with desktop search, have heard about index and they probably have some information about it's origin; but it seemed very strange for me that at the end of article it says:
Although it is true, but i can't imagine how would life be without computer index. We probably should have relied on directories like Yahoo directory as 90s

The human-made index has nuance and subtext that the computer version simply can't achieve.