Types of Data Transmission
In digital devices, there are two methods to transmit data
1. Serial transmission: It sends one data-bit at a time over a single channel.
2. Parallel transmission: It can sends multiple data-bits at a time over multiple channels.
In serial data transfer, there are two basic types of data transmissions
1. Synchronous Data Transmissions
2. Asynchronous Data Transmissions
1. Asynchronous Transmission

- In asynchronous transmission mode, the data transmitted character by character.
- Irregular gaps between the characters
- It is Less efficient and slower than the synchronous transmission.
- It uses start (0) and stop (1) bits. Stop bit (1) is transmitted at the end of each character which tells that character is transmitted.
- Asynchronous transmission also known as half-duplex.
2. Synchronous Transmission

- In synchronous transmission mode, the data transmitted block by block.
- Each block consists of many characters.
- It uses the clock to control the timing of bits.
- It is faster than asynchronous because No gap between the characters.
- For example, computer to printer communication.
- Synchronous transmission mode also known as Full-duplex.