2. Introduction: - Audio Devices: Audio devices allow you to play or record audio, which can be sounds and music. There are two types: Input and Output. -Audio Formats: An audio format is a file format for storing digital audio data on a computer system or electronic device. -Codec:A codec is a device or computer program capable of encoding or decoding a digital data stream or signal. There are two types loss codecs and lossless codecs. 3. -Input devices: they are devices that recive sound, and convert it into digital signals in the soundcard through the soundports. Examples: Microphones. 4. -Output Devices: They are the devices that emit digital signal transformed to sound by the soundcard by plugin it into the soundports. Examples:Loudspeakers and Headphones. 5. Mp3: Is an encoding format for digital audio which uses a form of lossy data compression. It is the most common audio format for consumer audio streaming or storage. Midi: Is a technical standard that describes the relation between and instrument and a computer. 6. WMA:Is an audio data compression technology developed by Microsoft. WAV:Is a Microsoft and IBM audio file format standard for storing an audio bitstream on PCs. 7. Loss codecs:Many of the more popular codecs in the software world are lossy, meaning that they reduce quality by some amount in order to achieve compression. Lossless codecs: There are also many lossless codecs which are typically used for archiving data in a compressed form while retaining all of the information present in the original stream.