0b101010

0b101010 is a binary literal used in several programming languages to denote a number written in base-2. The prefix 0b indicates that the digits following are to be interpreted as binary digits, rather than decimal, hex, or octal.

The sequence 101010 represents six bits: 1, 0, 1, 0, 1, 0. In decimal, this value is 42. It can also be expressed as hexadecimal 0x2A, and in ASCII the code 42 corresponds to the asterisk character (*).

In code, 0b101010 is an integer constant. Many modern languages support this syntax, including Python, JavaScript (ECMAScript 6 and later), Java, C++, Rust, and Go. The exact rules for digits after the prefix may vary by language (such as allowable digits or underscores for readability), but the underlying value remains the same.

The pattern 101010 is an alternating bit sequence. In 8-bit contexts, related patterns include 0b10101010 (0xAA) and 0b01010101 (0x55). Such patterns are commonly used as bit masks, test values for bitwise operations, or simple patterns in demonstrations and exercises involving binary arithmetic.