O

Objects executed at the operating system startup - A set of programs required for launching and correct operation of the operating system and other programs installed on your computer. Your operating system runs these objects during each startup. Some viruses infect startup objects and can cause an OS startup failure.
OLE object - An object linked or embedded into another file. Kaspersky Anti-Virus Personal scans such objects for viruses. For example, a Microsoft Excel spreadsheet embedded in a Microsoft Word document will be scanned by Kaspersky Anti-Virus Personal as an OLE object.
On-demand scan - A mode of program operation initiated by the user that performa a scan of files of all types resident on your computer.