Data & OSI Model

Data: Data is a collection of information which can be in the form of text, number, character or media. 

The OSI Model (Open System Interconnection)

The source computer sends data to the target computer. It is processed and transformed by different functions in the OSI layers.

During transmission of data, it can be also encryped and additional transmission-related information, which is called headers are added to it.

1. Application Layer: This layer provides the interface that enables application to access the network services.

2. Presentation Layer: This layer provides and ensures that the data is in a usable format and handles encryption and decryption.

3. Session Layer: This layer maintains the distinction between the data of separate applications.

4. Transport Layer: This establish a logical connection between the source and destination. It also specifies the TCP.

5. Network Layer: It decides which physical path the data will take. 

6. Data Link Layer: It defines the format of the data on the network.

7. Physical Layer: It transmits the raw bitstream over the physical network.