Boot Process Sequence of events that occurs between the time you turn on a computer and the time that it becomes ready to accept commands. Purposes • Runs a diagnostic test to make sure everything is working. • Loading the operating system, so the computer can carry out basic operations.
6 events of the boot process: Power up Start boot program Power-on self-test Identify peripheral devices Load operation system Check configuration and customization
Circuits The path from one component of a computer to another that data uses to travel. Circuits run between RAM and the microprocessor RAM and various storage devices
Silicon Chip Silicon is melted sand. The circuits are embedded into to keep them together.
Megahertz (mHz) A measurement used to describe the speed of the system clock. A megahertz is equal to one million cycles (or pulses) per second. 1.3 GHz means that the microprocessor’s clock operates at a speed of 1.3 BILLION cycles per second.
Pentium Name of the CPU. Pentium is the 5th generation of the Intel processor. Other generations were called • 80-88 • 286 • 386 • 486
RAM vs. ROM RAM ROM “Random Access Memory” “Read only memory” The ability of a storage device Drives can read data from to go directly to a specific disks, but cannot store new storage location without having data on them. One or more integrated to search sequentially from a beginning location. circuits that contain permanent instructions that Volatile the computer uses during the • Cannot hold data when the boot process. power is off. • Looses all data when power is lost.
Binary Number System A method for representing letters or numbers using only two digits, 0 and 1. Bit • Each 0 or 1 Byte • 8 bits Also referred to as Base 2 Binary Code.
Memory Measurements Bit Each 0 or 1 Byte 8 bits Kilobyte Approximately 1,000 bytes Exactly 1,024 bytes Megabyte Approximately 1 million bytes Exactly 1,048,576 bytes Gigabyte Approximately 1 billion bytes Terabyte Approximately 1 trillion bytes
Storage Devices Used to keep data when the power to the computer is turned off. Medium/media Location where data is stored.
Hard Disk Usually mounted inside the computer’s system unit. Can store billions of characters of data. Stated in forms of bytes: • Megabytes or Gigabytes etc
Magnetic Storage A fairly permanent type of storage that can be modified. Recording of data onto disks or tape by magnetizing particles.
Floppy Disk Round piece of flexible plastic covered with a thin layer of magnetic oxide and sealed inside a protective covering. May be referred to as a floppy” 3½ disk capacity is 1.44 MB or 1,440,000 bytes
Floppy Disk Options Formatted Preparing the disk for use by the computer. Write-protected Setting the disk so that it can not be written to by the computer.
Zip Disk Floppy disk technology manufactured by Iomega in late 1994. Available in 100 MB and 250 MB versions
Digital Audio Tape Method of storing large amounts of data on tape using helical scan technology to write data at high densities across the tape at an angle. Digital Audio Tape (DAT) is a recordable audio format conceived by the Japanese in mid 80’s
Optical Storage Means of recording data as light and dark spots on CD or DVD. Reading is done through a low-power laser light.
CD-ROM “CD – Read Only Memory” Also called CD-R CD-Read Storage device that uses laser technology to read data that is permanently stored on compact disks.
CD-RW “CD-Read Write” A storage device that reads data from CD’s and also can write data to CD’s. Similar to a CD-ROM, but has the ability to write to CD.
DVD-ROM “Digital Video Disks – Read Only Memory” Reads data from CD’s (audio & data) and DVD’s (data or movie).