Octal to binary conversion involves converting numbers from base-8 (octal) to base-2 (binary). Here's a step-by-step explanation: Octal Number System The octal number system uses 8 digits: 0-7. Binary Number System The binary number system uses 2 digits: 0-1. Conversion Steps 1. Break down the octal number into individual digits. 2. Convert each octal digit into its binary equivalent using the following mapping: | Octal Digit | Binary Equivalent | |-------------|-------------------| | 0 | 000 | | 1 | 001 | | 2 | 010 | | 3 | 011 | | 4 | 100 | | 5 | 101 | | 6 | 110 | | 7 | 111 | 3. Combine the binary equivalents to form the final binary number. Example Convert the octal number 345 to binary: 1. Break down the octal number: 3, 4, 5. 2. Convert each digit to binary: - 3 = 011 - 4 = 100 - 5 = 101 3. Combine the binary equivalents: 011100101. Therefore, the binary representation of the octal number 345 is 011100101.