robust精力充沛的; 坚定的; 粗野的，粗鲁的; 需要体力的
underlying 潜在的，含蓄的; 基础的; 表面下的，下层的; [法] 优先的;
boilerplate 样板文件; 公式化，陈词滥调
under the hood.在后台，在底层
comprise 包含，包括; 由…组成; 由…构成
persistence持续; 坚持不懈; 执意; 留存，（萤光屏上余辉的）保留时间;.
repo仓库(仓库也可以叫做项目)
migrations迁移，移居( migration的名词复数 )
Android architecture components are a collection of libraries that help you design robust精力充沛的; 坚定的; 粗野的，粗鲁的; 需要体力的;, testable, and maintainable apps. Start with classes for managing your UI component lifecycle and handling data persistence持续; 坚持不懈; 执意; 留存，（萤光屏上余辉的）保留时间;.
Manage your app's lifecycle with ease. New lifecycle-aware components help you manage your activity and fragment lifecycles. Survive configuration changes, avoid memory leaks and easily load data into your UI.
Use LiveData to build data objects that notify views when the underlying 潜在的，含蓄的; 基础的; 表面下的，下层的; [法] 优先的;database changes.
ViewModel Stores UI-related data that isn't destroyed on app rotations.
Room is an a SQLite object mapping library. Use it to Avoid boilerplate 样板文件; 公式化，陈词滥调 code and easily convert SQLite table data to Java objects. Room provides compile time checks of SQLite statements and can return RxJava, Flowable and LiveData observables.
Additional resources
Try Android room with a view, a codelab that shows how to use Room, ViewModel, and LiveData.
The Sunflower demo app demonstrates best practices with architecture components.
The Github Browser Sample uses architecture components with Dagger 2.
Our Github repo仓库(仓库也可以叫做项目) contains other small samples demonstrating how to use architecture components.
Understanding migrations迁移，移居( migration的名词复数 ) with Room
How database migration to Room works under the hood.在后台，在底层
