This document discusses various oxygen delivery devices and their appropriate usage. It begins by outlining important factors to consider when selecting an oxygen delivery system, such as the concentration required, achieved concentration, accuracy, and patient comfort. Several common devices are then described in detail, including nasal cannulas, simple masks, partial and non-rebreather masks, venturi masks, tents/hoods/incubators, bag-valve-masks, pulse dose cannulas, and concentrators. Each device is evaluated based on the concentration delivered, flow rate, advantages, disadvantages, and appropriate nursing interventions.