Optics: : [op-tiks] - noun. A branch of physics that studies electromagnetic radiation (for example, light and infrared radiation), its interactions with matter, and instruments used to gather information due to these interactions.Optics includes the study of sight. branch of physics that studies electromagnetic radiation (for example, light and infrared radiation), its interactions with matter, and instruments used to gather information due to these interactions.
By 1924, the National Flag Conference, under the leadership of the American Legion and the Daughters of the American Revolution, changed the Pledge's words, 'my Flag,' to 'the Flag of the United States of America.'
pledge (plural pledges) A solemn promise to do something. Something given by a person who is borrowing money etc to the person he has borrowed it from, to be kept until the money etc is returned. A person who has taken a pledge of allegiance to a college fraternity, but is not yet formally approved.