Data is missing from master to slave. Slave is working fine

what is the reason if some tables data is missing in slave but this data is available on master server when we check the slave is working fine.

1. May be its there is problem in Mysql_bin.log because the slave is read the data statement from there may be there is problem with master its not writing in Mysql_bin.log file.

What you says guys. Help me out on this.