HOW IT WORKS …

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WHAT IS A COMPUTER?

• A COMPUTER IS AN ELECTRONIC DEVICE FOR RETRIEVING, STORING AND PROCESSING DATA ACCORDING TO A VARIABLE PROGRAM

• COMPUTERS ARE NOT AS SMART AS WE MAKE THEM TO BE, THEY CANNOT FUNCTION OUTSIDE OF WHAT WE TELL THEM TO DO

WHAT’S INSIDE?• MOTHERBOARD: A CIRCUIT BOARD WHICH

CONTAINS THE PRINCIPAL COMPONENTS OF A COMPUTER AND PORTS FOR OTHER CIRCUIT BOARDS TO BE CONNECTED/SLOTTED

• A MOTHERBOARD WILL FUNCTION VERY SIMILARLY TO A LEGO BOARD

CPU

• CENTRAL PROCESSING UNIT

• BASICALLY FUNCTIONS AS THE “BRAIN” OF THE COMPUTER

• EVERYTHING GOES THROUGH THE PROCESSOR

• FUNCTIONS:

1) INPUT/FETCHES DATA

2) PROCESSES/DECODES DATA

3) OUTPUTS/EXECUTES DATA

4) STORES DATA

CPU (THINGS TO KNOW)

• PROCESSING SPEEDS, READS BITS OF INFORMATION AT A TIME

• HERTZ – PIECES OF INFORMATION PER SECOND

• EX: 2.2 GHZ (2.2 BILLION “PIECES” PER SECOND)

• MULTI-CORE PROCESSORS

CPU (WHAT’S INSIDE OF IT?)

• TRANSISTORS: BASICALLY SWITCHES THAT RUN AND ARE PROGRAMMED ACCORDING TO AN ELECTRIC CURRENT

• CIRCUITED IN A WAY THAT REPRESENTS A DECISION TREE

• ENIAC (1945)

• MOORE’S LAW: THE NUMBER OF TRANSISTORS IN A SPACE WILL DOUBLE EVERY TWO YEARS

MEMORY (RAM)

• THERE ARE TWO TYPES OF MEMORY: RAM VS. STORAGE

• RAM (RANDOM ACCESS MEMORY)

• COMPARATIVE TO “WITHIN ARM’S REACH” MEMORY STORAGE

• “RANDOM” BECAUSE COMPUTER CAN ACCESS ANYTHING ON RAM QUICKLY, AS OPPOSED TO FINDING IT’S PLACE LIKE ON A CASSETTE PLAYER

• MEMORY IS LOST WHEN COMPUTER IS SHUT DOWN, DEPENDENT ON ELECTRICITY, CONSTANT CURRENT

• MORE RAM, GENERALLY MEANS FASTER COMPUTER (512 MB, 4 GB)

MEMORY (HARD DRIVES)

• STORAGE MEMORY: LONG-TERM DATA STORAGE, COMPARATIVE TO BOOKSHELVES, CLOSETS

• RUNS ON ELECTRICITY BUT DATA IS NOT ERASED WHEN IT IS POWERED OFF, “PERMANENTLY WRITTEN”

• MUCH BIGGER CAPACITY, BUT MUCH SLOWER SPEEDS

• GENERALLY MORE THAN 256 GBS, 500 GBS, 1 TB

MEMORY (HARD DRIVES)

• SATA (MECHANICAL) VS SSD (NO MOVING PARTS – RANDOM ACCESS)

*SSD STORES DATA IN TRANSISTORS CALLED FGMOSFET (FLOATING GATE METAL OXIDE SURFACE FIELD EFFECT TRANSISTOR)

INPUT DEVICES

• INPUT DEVICES ALLOW US TO COMMUNICATE WITH OUR COMPUTERS BY CONVERTING INFORMATION INTO A FORMAT THAT THE COMPUTER CAN UNDERSTAND (1’S AND 0’S)

• KEYBOARD, MOUSE, MICROPHONE, TOUCH SCREEN, WEBCAMS, ETC.

OUTPUT DEVICES

• OUTPUT DEVICES ALLOW COMPUTERS TO COMMUNICATE WITH US IN A WAY THAT WE WOULD UNDERSTAND

• MONITORS, SPEAKERS, PRINTERS, ETC.

HARDWARE VS. SOFTWARE

• HARDWARE IS RIGID, AND CANNOT PERFORM TASKS THAT WERE NOT ORIGINALLY DESIGNED FOR THE DEVICE

• SOFTWARE IS FLUID AND CAN BE EASILY CHANGE

• SOFTWARE IS A SET OF INSTRUCTIONS THAT TELL THE HARDWARE OF THE COMPUTER HOW TO BEHAVE