IT
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IT
Information technology
What is information technology?
Information Technology(IT) The use of digital technology,like computers and the Internet,to store and process data into useful information
Algorithm
A series of steps that solve specific problems.
Cryptography
The art of writing and solving codes.
GNU
Open source
Anyone could modify and share it.
Operation System.
software
compiler was invented by Admiral Grace. Hopper compilers made it possible to translate human language via a program language into machine code in case you didn’t totally catch that we’ll talk more about compilers later. now learning programming languages is accessible for almost anyone anywhere. that scares you don’t worry we’ll help you every step of the way but for now let’s get back to the evolution of computers.
who knows what the future holds
computer language
0 + 1 = ?
simple math problem 0 plus 1 equals what?
Binary system The communication that a computer uses, also known as a base-2 numeral system. We group binary into 8 numbers or bits. Technically,a bit is a binary digit.
A group of 8 bits is referred to as a byte.
Each byte can store one character, and we can have 256 possible values thanks to the base-2 system(2^8).
01101000-h 01100101-e 01101100-I 01101111-o
computer talk this byte can mean something like the letter C and this is how a computer language is born
What does the following translate to?
01101000 01100101 01101100 01101100 01101111
something we’d be able to recognize what does the following translate.
make sure you understand the concept before moving on.
Character encoding
you can think of character encoding as a dictionary it’s a way for your computer’s to look up which human character should be represented by a given binary value.
The first character in the ASCll to binary table–a lowercase a -maps to 01100001 in binary.
RGB
that’s used in a lot of computers RGB or red green and blue model.
very cool
with just eight combinations of zeros and ones were able to represent everything that you see on your computer from a simple letter A to the very video that you’re watching right now.
Logic gates
we’ll discuss how we actually generate the zeros and ones.
Allow our transistors to do more complex tasks,like decide where to send electrical signals depending on logical conditions.
Digital Logic How to Count in Binary?
that you understand how computers count in binary we’ve shown you simple look-up tables that you can use like the ASCll to binary table.
you’ll need to know how binary works.
Decimal form : Base-10 system 0123456789
Computer Architecture Layer
Abstraction
To take a relatively complex system and simplify it for our use
error messages
hardware
The Modern Computer Intro to Computer Hardware
desktop
components
Ports Connection points that we can connect devices to that extend the functionality of our computer
CPU (Central Processing Unit) The brain of our computer,it does all the calculations and data processing
RAM (Random Access Memory) Our computer’s short-term memory
Hard drive Holds all of our data,which includes all of our music,pictures,applications
Motherboard The body or circulatory system of the computer that connects all the pieces together
computer can only communicate in binary using ones and zeros our computers
our computers speak in machine language but we of course speak in human languages like English Spanish Mandarin Hindi you get the idea if we want to communicate with our machines we have to have some sort of translation dictionary just like if I wanted to say something in Spanish.
well our computers have a built-in translation book.
Programs
Instructions that tell the computer what to do
1.Get two slices of bread. 2.Put peanut butter on one slice. 3.Put jelly on another slice. 4.Combine the two slices of bread.
on 1
off 0
Memory Controller Chip
MCC
Address bus
Cache
There are 3 different cache levels in a CPU: L1,L2, andL3.
L1is the smallest and fastest cache.
Clock wire
Calculations
Clock cycle
Clock speed
Clock speed The maximum number of clock cycles that it can handle in a certain time period
3.40 gigahertz is 3.4 billion cycles per second.
Overclocking
Adding Subtracting Copying data
instruction sets are hard-coded into out CPU.
Replacing failed hard disks Upgrading RAM modules Installing video cards
Intel AMD Qualcomm
Intel Corei7 AMD Athlon Snapdragon 810 AppleA8
When you select your CPU, you’ ll need to make sure it’s compatible with yourmotherboard–the circuit board that connects all your components together.
cpu socket
Land grid array(LGA) Pin grid array(PGA)
There are lots of types of RAM, and the one that’s commonly found in computers is DRAM, or dynamic random-access memory.
There are also different types of memorysticks that DRAM chips can be put on. The more modern DIMM sticks, which usuallystands for Dual Inline Memory Module, have different sizes of pins on them.
SDRAM
Synchronous DRAM
In today’s system, we use another type of RAM, called double data rate SDRAM or DDR SDRAM for short.
DDR1 DDR2 DDR3 DDR4
Motherboards
total boss
chipset
Northbridge
Southbridge
Peripherals
External devices we connect to ourcomputer,like a mouse,keyboard,and monitor
Expansion slots Give us the ability to increase the functionality of our computer
PCI Express
Peripheral Component Interconnect Express
Form factor
ATX
Advanced Technology eXtended
ITX
Information Technology eXtended
Storage
Data sizes
8bits 1 byte
1,024 bytes
Hard drive
Hard disk dives
HDD
RPM
Revolution per minute
Solid state drive
SSD
ATA
Serial ATA
SATA
NVM Express
NMe
Power Supplies
DC direct current
AC AC or alternating current
Information which is normally listed underneath or on the side.
cables
power cable
to understand electricy let’s use the example of water pipes.
the higher the pressure the more water there will be when it comes electricity we refer to the pressure as Voltage.
As a general rule, be sure to use the proper voltage for your electronics.
Amperage
AMPs
Wattage The amount of volts and amps that a device needs
You can power most basic desktops with a 500W power supply.
Peripherals
todo
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