Question: I have been scouring the internet for a few days and have not been able to find what I am looking for, so I decided to come here and ask you fine people if you have an answer to my line of inquiry. 

I have been looking for what a group of books is called and why it is named so, id est, the type of series that it is and why it is called that. 

For example, chronicles are multiple pieces of literature that take place in the same place or involve the same character(s). Words like chronicle and saga are examples of what I am looking for.

Answer: 
Consider [**library of books**](http://www.merriam-webster.com/dictionary/library).

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> **library**: 
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1.

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> **a**: a place in which literary, musical, artistic, or reference materials (as books, manuscripts, recordings, or films, are kept for use but not for sale
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> **b**: a collection of such material
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2.

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> a collection resembling or suggesting a library
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3.

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> **a**: a series of related books issued by a publisher
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> **b**: a collection of publications on the same subject
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These are the name for a series of books. Most use the typical Greek prefixes, but a few variants have popped up in my research. Some among the academia have yet to acknowledge or agree on the exact names, but here it is.
One book- A book. Or a Monology or a Solo.  

Two Books- A duology,or a diology or duet 
Three books- A trilogy, or trio.
Four books- A Cycle, or a Quartet Or a Tetralogy 
Five books- A Pentalogy or a Quintet 
Six books- A Hexlogy or a or sextet
Seven books- A Heptalogy or a Wonder (Seven Wonders of the World)
Eight books- A Octalogy or a octet
Nine books- A Nonalogy or nexus or nonet
Ten books- A Decalogy or dectet or a decade of books!