fail over type - transaction vs select ? looks the same

hi guys,

just need to understand abit more on what is the different between the failover type of the TAF when one specify TRANSACTION or SELECT.

I see no difference from the abstract:

Currently, TAF will fail over standard SQL SELECT statements that have been caught during a node crash in an in-flight transaction failure. In the current release of TAF, however, TAF must restart some types of transactions from the beginning of the transaction.

The following types of transactions do not automatically fail over and must be restarted by TAF:

Transactional statements. Transactions involving INSERT, UPDATE, or DELETE statements are not supported by TAF.