need your help

[t liu]

when hive craete a table ,we need set hql like this

 'CREATE TABLE page_view(viewTime INT, userid BIGINT,
                    page_url STRING, referrer_url STRING,
                    ip STRING COMMENT 'IP Address of the User')
    COMMENT 'This is the page view table'
    PARTITIONED BY(dt STRING, country STRING)
    STORED AS SEQUENCEFILE;'

in this hql,file type is 'STORED AS SEQUENCEFILE' , the question is:

how many file types can we set? what different between them ?

I learned hive about a week , don't lauch at me .....