Binary-coded decimal (BCD) is a digital representation of decimal numbers in which each digit is represented by its own binary sequence. BCD encodes each decimal digit with a four-bit binary value, as shown in the following table:
| Decimal | BCD |
|---|---|
| 0 | 0000 |
| 1 | 0001 |
| 2 | 0010 |
| 3 | 0011 |
| 4 | 0100 |
| 5 | 0101 |
| 6 | 0110 |
| 7 | 0111 |
| 8 | 1000 |
| 9 | 1001 |
For example, the decimal number "246" would be represented in BCD as "0010 0100 0110". BCD is often used in computer systems to store and manipulate decimal values because it is more efficient and simpler than using other representations such as pure binary or ASCII. It is also commonly used in digital circuits, particularly in embedded systems and microcontrollers, because it is easy to convert between BCD and other number representations using simple logic gates. However, BCD is not as widely used as it once was because modern computers often use more efficient representations such as two's complement or floating-point numbers.