Book excerpt: This book explains how the binary works and how it is used by computers to represent information including positive and negative integers, characters and real numbers. It explains the logical and bitwise operations used to manipulate information and perform arithmetic. We also briefly look at how computers store this information in memory and secondary storage, and how it can be transmitted between computers. Topics covered include: INTRODUCING NUMBER BASES AND BINARY CONVERTING FROM BINARY TO DENARY AND VICE-VERSA How to Convert a Binary Number to Denary How to Convert a Denary Number to Binary HOW COMPUTERS GROUP BINARY DIGITS A Closer Look at Bytes A Closer Look at Words * Word alignment, word alignment and packing, byte ordering and endianness Addresses BOOLEAN OPERATIONS AND LOGIC GATES Fundamentals of Boolean Algebra * NOT, AND, OR, XOR, NAND, NOR, NXOR Combining Logic Gates * NOT, AND, OR, XOR, NOR using NAND logic Logical Versus Bitwise Operations Using Bitwise Operations to Set, Clear, Flip or Test Bits * Setting bits, inverting bits, clearing bits, testing bits ADDING AND SUBTRACTING IN BINARY Adding Binary Integers * The column addition method of adding denary numbers and adding binary numbers, implementing binary addition using logic gates Subtracting Binary Integers * The column subtraction methods of subtracting denary numbers and subtracting binary numbers, implementing binary subtraction using logic gates SHIFT OPERATIONS Left Shift Right Shift Circular Shifts MULTIPLICATION AND DIVISION IN BINARY Multiplication * Multiplying by a power of 2, column multiplication, Russian peasant multiplication algorithm, multiplication in hardware Division * Dividing by a power of 2, denary long division, binary long division, algorithm for binary long division, division in hardware REPRESENTING CHARACTERS AND STRINGS OF CHARACTERS Representing Individual Characters * ASCII, extended ASCIIs, BCDIC and other early character encodings, EBCDIC, Unicode Representing Strings of Characters * Terminated strings, length-prefixed strings, other string representations REPRESENTING TEXT AND GRAPHICS ON SCREEN Text Mode Displays Bitmap Displays PARITY CHECKING What is a Parity Bit Even and Odd Parity Advantages, Disadvantages and Limitations of Using Parity Checking Parity's Use in RAID Storage Devices Unused Parity Bits SIGNED INTEGERS Offset Binary Signed Magnitude Representation One's Complement Two's Complement Other Representations of Signed Numbers * Base -2, signed-digit representation REAL NUMBERS Fixed Point Representation Floating Point Representation Rational Data Type Logarithmic Number Systems DENARY ENCODINGS AND DECIMAL DATA TYPES Why Use Denary Representations of Real Numbers? Binary Encodings of Denary * Serial decimal, two-out-of-five, bi-quinary, character-based encodings of denary, binary-Coded Decimal (BCD), Chen-Ho Encoding, Densely Packed Decimal (DPD) and excess-3 Decimal Data Types * Which numbers can be exactly represented in fixed and floating point? * How inexact? * Issues with inexact representation * Decimal representation DATA STRUCTURES Structs Arrays Linked Lists and More Complex Structures * Limitations of arrays, introducing linked lists, singly and doubly linked lists, more complex data structures TYPES OF COMPUTER MEMORY Magnetic-Core Memory and Core Rope Memory RAM * DRAM and SRAM ROM * Mask-programmed ROM, PROM, EPROM, EEPROM, Flash memory SECONDARY STORAGE Sequential Storage * Punched tape, magnetic tape Random Access Storage * Magnetic disk, optical disk, solid state drives, flash memory and cloud Storage MEASURING MEMORY AND STORAGE DIGITAL COMMUNICATIONS Serial Communication Parallel Communication MEASURING TRANSFER RATES Baud