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Number guides

Short guides on bases, bits and two's complement.

What is a number systemA simple explanation of positional notation and how bases work.Two's complement and negative numbersHow computers represent negative numbers in a fixed bit width.Why hexadecimal is used in programmingWhy hex is so common in programming.Understanding bitwise operationsA rundown of bitwise operations: AND, OR, XOR, NOT and shifts.Bits, bytes and data unitsAn overview of bits, bytes and data units like KB, MB and GB.Octal and file permissionsUnderstanding Unix file permissions like chmod 755 in octal.IP addresses and binaryHow an IPv4 address is expressed as 8-bit octets and binary.Endianness (byte order)Big-endian and little-endian, the order multi-byte numbers are stored.Unicode and code pointsHow characters, code points and UTF-8 encoding relate.Floating-point representationHow IEEE 754 floating-point numbers are stored in bits.