This question already has an answer here:
SQL Server backups contain meta-data about the size of the original log (LDF) file.
So if you backup a database that has a 5GB LDF file, when you restore it, you will get an (empty) 5GB LDF file. This often isn't needed (because the log file of the restored database contains practically nothing)
Often this causes problems with database restores on busy dev servers with not much space left if people *cough* haven't been too careful about shrinking log files before making the backup.
Is there any way to restore a SQL Server backup but tell it "Dont bother making that empty 5GB LDF file, thanks" ?