![yaooqinn](https://badgen.net/badge/Hello/yaooqinn/green) [![Closes%20#321](https://badgen.net/badge/Preview/Closes%2520%23321/blue)](https://github.com/yaooqinn/kyuubi/pull/321) ![172](https://badgen.net/badge/%2B/172/red) ![1](https://badgen.net/badge/-/1/green) ![1](https://badgen.net/badge/commits/1/yellow) [&#10088;?&#10089;](https://pullrequestbadge.com/?utm_medium=github&utm_source=yaooqinn&utm_campaign=badge_info)<!-- PR-BADGE: PLEASE DO NOT REMOVE THIS COMMENT -->

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### _Which issue are you going to fix?_
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Fixes #${ID}

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Add terminology documentation for better understanding both for users and devlopers

### _How was this patch tested?_
- [ ] Add some test cases that check the changes thoroughly including negative and positive cases if possible

- [x] Add screenshots for manual tests if appropriate
![image](https://user-images.githubusercontent.com/8326978/106347018-278d9880-62f6-11eb-8dcf-8125ce69c403.png)

- [ ] [Run test](https://kyuubi.readthedocs.io/en/latest/tools/testing.html#running-tests

) locally before make a pull request

Closes #321 from yaooqinn/terminology.

2a6c7e7 [jhx1008] Add Terminologies Documentation
Authored-by: jhx1008 <jhx1008@gmail.com>
Signed-off-by: Kent Yao <yao@apache.org>