HTML5提供的客户端数据存储方式
- 
Web Storage
- localStorage
 - sessionStorage
 
 - Web SQL Database
 
Web SQL Database
The Web SQL Database spec gives developers a simple but powerful JavaScript database API to store persistent data in a local SQLite database.
'INSERT INTO entries (date, calories, food) VALUES (?, ?, ?);', This is  the  statement  that  will  be  executed.  The  question  marks  are  data placeholders.
[date, calories, food], This is an array of the values being sent to the database. They correspond by position with the data placeholder question marks in the SQL statement.