At the end of the backup process, any transactions that have completed while the backup was running will be brought into the backup. The recovery step of the restore process is when the transactions that were open during the backup are rolled forward or rolled back, as appropriate.
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning