All computers share the same four things:input,storage,prossesing and output.
Input is what you do with the computer,storage is like memory,prossesing is taking-
info and aplying algorithoms
to help the computer understand the info,
output is what happens!
As again...
1.Input:key bords, touchscreens
2.Storage:files
3.procssing:CPU
4.Output:screen,robots,sound
There are many electrical bits, a few of those bits make a circut,NOT CIRCUT:a not circut gives you the opossit,
a and circut gives you a 0 at least one of the two"inputs"is a 0,it wil only give you a
1 if both of the "inputs"are 1's!
AN 8 BIT ADDER:A 8 bit adder has 16 inputs!It can do up to an eqation wich equals 11111111,or255!
back in the day,8 bit adders were the size of a room!.smaller computers and circuts are faster cause the electricity has less way to travel
CSS stands for cascading style sheets,CSS saves you a lot of work.
An internal style sheet you place in the head sectoion,it allters the whole page,
Inline style only aplys to your line,External styling is to your whole webpage!
Hard ware is phisical stuff like circuts,wires and other stuff,soft ware is stuff you dont see or touch
The CPU controls the hard ware and soft ware, the CPU has many small circuts in it
but the magic how it knows when to use the programs.
OS..........is the master program that manages how the soft ware uses the hard ware of a computer
OS examples are windows,android,ios,linux.the OP lets you install programs,
and dicides if a program can interact with the CPU, and acsses the input and output sistom.
IN EVEREY COMPUTER THERE IS AN OS
yay for........................................................................COMPUTERS!!!!!!
Ip stands for Internet proticall so an IP adress stands for Internet Proticall adress.
An IP adress has numbers insted of letters,the numbers are represented in bits,
with 32 bits and 8 per part(8 p.p.),its like this,country/network,region/more network,subnetwork,and divice
Thats IPV 4,but it only provides network for 4 billion divices,we are now in the middle of transfering......
......to IPV 6,with 128 bits 16 bits per part,it can provide sirvice for 340 undicilion divices,thats more than enough...
for every grain of sand on earth to have its own divice!DNS stands for Domain Name Systom, and turns every thing into numbers
External scripts are practical when the same code is used in many different web pages. JavaScript files have the file extension .js. To use an external script, put the name of the script file in the src (source) attribute of a script tag
Info travels in things called packets,images and things are sent in many packets
routers controll the flow of packets and moniter conjunctions.its fault tolerent and reliable
TCP(trnsmission controll protocall) tells you if all your data has come,TCP and routers are scale-able.
H level
Is easy for programers to understand
Contains engish words
L level
The computers own language
binary numbers in ones and zeros
| Compiled | V.S. | Scripted |
|---|---|---|
| code with these langauges are converted to binary or machine language beforebthey can be run |
code is written in these languages that are not compiled first. code is interpreted and exicuted in therun time enviroment |
java script works together with HTML/CSS to create web applications.
HTML provides the content
CSS provides the presentation
Java script programs the beheivior
UI = user interface
UX = user experiance
| cannot read files from the clients machine | can only connect to another server | cannot close window that does not open |
|---|
Let and Var control variables
DOM = Document object model
HTML parser
CSS parser
JS engine
An array is a variable that can hold Two+ variables at a time
example
| Camel | Non camel |
|---|---|
| myVeryLongName | myverylongname |
true or false operators are using things with boolian conditions
HTML ASCII
A FOR loop runs through a statement a sertain number of times ... Needs a counter
The first statement in a For loop is executed once before the execution of the block o' code
The second statement is executed onetime before the execution of the code block
The third statement is execuded everywhere after the code block has been executed.
Normally you will use statement 1 to initialize the variable used in the loop (i = 0).
This is not always the case, JavaScript doesn't care. Statement 1 is optional.
You can initiate many values in statement 1 (separated by comma)
Often statement 2 is used to evaluate the condition of the initial variable.
This is not always the case, JavaScript doesn't care. Statement 2 is also optional.
If statement 2 returns true, the loop will start over again, if it returns false, the loop will end.
Often statement 3 increments the value of the initial variable.
This is not always the case, JavaScript doesn't care, and statement 3 is optional.
Statement 3 can do anything like negative increment (i--), positive increment (i = i + 15), or anything else.
Statement 3 can also be omitted (like when you increment your values inside the loop):
STRING:is a line of charicters
NULL:is for unknown values
UNDEFINED:is where the computer doesent know what what type it is
OBJECT:is for more complex stuff
SYMBOL:is for unique identifiers
An object has properties and functions
classes are blueprints for objects
Database Notes