| Open system interconnection | ���� ������ |
| Opening a file | ���� ������ |
| Operating system | ���� ����� |
| Operating system disk | ���� ����� �좴 |
| Operation analysis | ������좴� ���� |
| Operation centre | ������좴 ���� |
| Operation code | ������좴� ������ |
| Operation personal | ������좴 ܽ��� |
| Operation, arithmetical | ����좴� ������ |
| Operation, binary arithmetic | �� ����좴� |
| Operation, binary boolean | �� ������ ������ |
| Operation, complementary | ������ ������ |
| Operation, computer | �������� ������ |
| Operation, if - then | ����������� ������ |
| Operation, logical | ���� ������ |
| Operation, NOR | ��� ����� ������ |
| Operational management | ������좴 �������� |
| Operations research | ������좴 �� |
| Operator | ���������� / �������� |
| Operator, machine | ����� ���������� |
| Optical character | ���� � |
| Optical character reader | ���� �� ��� |
| Optical communication | ����� ���� |
| Optical laser disk | ���� ���� �좴 |
| Optical mark reader | ����� ��� ��� | |