Originally the term referred to people who used a razor blade and/or fingernail clippers to "hack" or roughly cut parts in electronics such as the traces on circuit boards, legs of diodes etc. Police scanners were "hacked" in order to add more memory, remove CPU processors , speed up scanning by "hacking" the crystal oscillator and replacing with faster ones. Thes methods are directly related to why computers now have more RAM, and are faster. Some of the old (and I do mean old) "hackers" devised a system in the 1960s to simultaneously send voice and data over a phone line using frequency phase shifting and filtering. A similar process used later by DSL.
"Hacking" and "Modding" evolved into things such as examining the programming of a thing. Beginning with noticing things such that by pressing certain keys or combinations of keys in certain secquences on a device could produce certain results. Following the era of IBM's "Big Blue" chess tournament, AT&T introduced the "unbeatable Tic Tac Toe Computer, and exhibited it. I, I mean a "hacker" back then, was able to beat the computer with a sequence of key presses in order to "cheat" the computer out of a move. On many Shortwave radios, Police Scanners, even cell phones etc, certain key presses are used in the programming, and could be used to alter that programming.
The keys on a keyboard of a device are a "Matrix" Keyboards use a matrix with the rows and columns made up of wires. Each key acts like a switch. When a key is pressed, a column wire makes contact with a row wire and completes a circuit. The keyboard controller detects this closed circuit and registers it as a key press to the software.
I'm going to try to keep this understandable to readers ...
Software can emulate or act like hardware.
Example: a hardware modem versus a DSP/Digital Signal Processor modem, where a chip is programmed to act like the hardware....
So, later, the focus turned even more from "hacking" the actual electronics and hardware to software "hacking" through PROGRAMMING.
A "black hat" hacker is often referred to as a microcomputer user who attempts to gain unauthorized access to proprietary computer systems. Although that could be a "cracker" ... a person cracking passwords etc.
Most often people who call themselves "hackers" are called "wannabes" by the old-timers, and nowadays are often adolescents using a program they didn't write, by clicking a button they didn't create, to do what don't understand, in an attempt to disrupt something they don't know how to fix.
"White Hat" hackers are the "good guys" like ... Like the old-timers who vastly improved what computers are capable of doing, and the ones currently trying to improve security by locating and preventing weaknesses.
This Answer is dedicated to the memory of Bill Cheek, author, The Scanner Modification Handbook series, and his BBS and Fidonet terminal (prior to "The Internet") Good man, Good freind to many... May he R.I.P.
On your computer, highlight the website in the little bar it's in. Press and hold Ctrl and press C and let go of each. Now it's copied. To paste go to the place you want to put the link and put your cursur there and then press and hold Ctrl and then press V and let go. Now you can click on it!
Application of induction motor in industry?
Induction motor used in industries for variable speed machines . Induction motor has always lagging power factor. Less cost compared to syn. Motor.
An Oldham coupling is a flexible shaft coupling that consists of two hubs (each with a fin or tenon) and one midsection (with grooves that fit those fins, one on each side of the midsection, and perpendicular to one another).
The Oldham coupling is an outstanding design for torque transmission between two shafts which might be slightly misaligned. The coupling accommodates this misalignment, while maintaining homokinetic motion (the two shafts rotate at the same speed at all times), and while exerting only very small reactive forces (resistance to accommodation of the misalignment, exhibited as sideward forces on the shafts).
More information on Oldham couplings can be found at www.oepcouplings.com.
How to write Resume for civil engineers?
For an engineer job you have to consider writing your extraordinary skills that make you a perfect communicator or link between engineers, contractors, clients, and management.
Your resume should also showcase your creative ideas, your technical skill, your awareness to latest technology, and your imaginative methods to improve efficiency.
To get some samples of civil engineers resume, see the related link below.
What is status of a circuit that is complete and unbroken with flowing electric current?
A circuit that is complete and unbroken with flowing electric current normally has steady supply of voltage with no broken links. Electrical energy flows to light up a bulb or do similar work. Its status is complete, nothing else is needed.
What is Difference between static and dynamic website?
Static Websites
Static means "constant--never changing". A static website contains Web pages with fixed content. Each page is coded in HTML and displays the same information to every visitor.
Dynamic Websites
dynamic is "changing". You can make dynamic changes to a database without having to shutdown the instance and restart for the changes to take effect. However, if you do not update the control file, when you shutdown and startup, the dynamic change is gone--it wasn't permanent.
What is the current in a circuit measured in?
The unit of current is the ampere (A), or amp for short. A thousandth of an amp is a milliamp (mA). One amp is equal to one coulomb of charge per second.
To save a file as a .html file:
1. Click on file
2. Then Save As
3. Change "Save as type:" to "All Files (*.*)"
4. In the "File name" input box enter (Your Pages Name).html
eg. Index.html
5. Press "Save"
Hope this helped you.
What year was the internet developed?
The first internet like network was probably the ARPANET.
In August 1962 computer scientist J. C. R. Licklider, sent out a memo, discussing the idea of an "Intergalactic Computer Network". The ideas in this memo are still used in todays internet. J. C. R. Licklider went on to work with the Advanced Research Projects Agency (ARPA), a division of the US Department of Defense. He helped with the ideas for what became the ARPA Network or ARPANET. The ARPANET's purpose was to link computer science departments at various universities, to improve the deliver of computing results. The contract for it's construction was given to BBN Technologies on 7 April 1969. ARAPANET's first version was completed within 9 months.
Tim Berners-Lee is often credited for creating the internet. In fact he and his team only created a mark-up language called Hyper-Text Mark-up Language or HTML and the protocol for it's transfer known as Hyper-Text Transfer Protocol or HTTP. HTML was simply a way of creating text documents that can link to other documents. This was called a hyper-link. Other tags were added to HTML through it's development to allow for images, input fields, raster plugins, applets and much more to allow more of the functionality we have in today's websites.
In 1980 Tim Berners-Lee, a physicist at CERN proposed and built a prototype of a system for sharing documents called ENQUIRE. In 1989, Berners-Lee wrote a memorandum proposing an Internet-based hypertext system. He finished a writing a HTML browser in 1990. In November 24, 1995 the first official HTML protocol was published.
So the answer is the ideas for the physical network began in 1962 and were realised in 1969. The ideas for today's de-facto internet document HTML began in 1980 and were made official in 1995.
Dc and ac analysis of Differential amplifier?
DC Analysis: For this analysis, frequency is made zero and the voltage of the source is increased in small steps from 0V.And the output voltage is plotted. So, finally we get a Vout vs Vin curve. AC Analysis: In this analysis, we choose an AC source. We keep the Offset voltage = 0V, AC voltage or small signal voltage = 2V (You can take any voltage you wish and it doesnt matter). So, to plot the ac response or frequency response of the circuit, increase the frequency in steps and note the output voltage. from this analysis , we can find the gain of the circuit over frequency.
How the waterfall model and prototyping model can be accommodated in the spiral process model?
Expalin different between waterfall model and prototyping model ? Expalin different between waterfall model and prototyping model ?
What software do you need to make a website?
You do not need software to make a website, though it does come in handy if you don't want to learn HTML/XHTML, JavaScript, and CSS. You can learn these three main languages, but it will take time and practice to make a good website. There are many websites out there that let you create a free "website" under a subdomain, such as mycoolsite.wordpress.com. Do a web search for "free website" and you'll find plenty of websites to try. Many of these offer paid upgrades such as you own domain (mycoolsite.com) or more advanced layouts.
Write a program in java to print amount of cable bill?
import java.io.*;
class Shop
{
String code[]=new String[20];
String name[]=new String[20];
float price[]=new float[20];
int i,j;
Shop()
{
i=0;
}
void getitem() throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter ItemCode:");
code[i]=br.readLine();
System.out.println("Enter ItemName:");
code[i]=br.readLine();
System.out.println("Enter UnitPrice:");
price[i]=Float.valueOf(br.readLine()).floatValue();
i++;
}
void printitem()
{
System.out.println("\n ItemCode\tItemName\tunitPrice\n");
for(j=0;j<i;j++)
{
System.out.println(code[j]+"\t\t");
System.out.println(name[j]+"\t\t");
System.out.println(price[j]+"\t\t");
}
}
}
class ShopOnl
{
public static void main(String args[]) throws IOException
{
BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
int ch=0;
Shop s=new Shop();
while(ch!=3)
{
System.out.println("1.Get Item");
System.out.println("2.View Bill");
System.out.println("3.Quit");
System.out.println("Enter your choice");
ch=Integer.parseInt(br.readLine());
switch(ch)
{
case 1:
s.getitem();
break;
case 2:
s.printitem();
break;
case 3:
System.out.println("Thank you! visit again");
break;
}
}
}
}
What are the function of ammeter?
The purpose of an ammeter is to sense and display the magnitude of the current
flowing through it. When connected in series with a branch of an electrical circuit,
the meter displays the magnitude (and direction) of the current in that path ... which
you can't otherwise tell just by looking at the circuit.
Why getch is used at the end of every c program?
getch() takes one char from keyboard but it will be invisible to us. in other words we can say that it waits until press any key from keyboard.
getch() is a function which has its protype defined in conio.h header file.
it is basically used to take input a single characterfrom keyboard. and this char is not displayed at the screen.
it waits until itn gets a input that's why it can be used as a screen stopper.
Write a program to compute factorial of a number on 8051?
FOR NO'S TILL 8 ONLY Example for Number 4
4!=4*3*2*1 which is = 24
MOV R1,#04
MOV R0,#04
MOV A,R0
CALL:DEC R0
MOV F0,R0
MUL AB
DJNZ R1,CALL
LCALL 0003
SHARAD KOTHARKAR
What is the importance of C language?
A C program is basically a collection of functions that are supported by the C library.we can continuously add our own functions to C library.with the availibility of a large number of functions, the programming task becomes simple......
How do you identify carbon resistor using colour code?
To identify the value of a carbon resistor using colour code use the following table...
0 - Black
1 - Brown
2 - Red
3 - Orange
4 - Yellow
5 - Green
6 - Blue
7 - Violet
8 - Grey
9 - White
... and look at the bands. The first two bands will be the digits, and the third band will be the multiplier. For instance, Brown - Red - Orange will be 12000 ohms, where the 1 is the first band, the 2 is the second band, and the three 0's is the third band.
If the third band is Gold or Silver, then the multiplier is 0.1 or 0.01 respectively. For instance, Brown - Red - Gold would be 1.2 ohms, and Brown - Red- Silver would be 0.12 ohms.
If there is no fourth band, the resistor is +/- 20%. If the fourth band is Silver, the resistor is +/- 10% and, for Gold, +/- 5%.
Some high end resistors have more bands. The 1% resistor will have a third digit band, and some resistors will have a band indicating temperature coefficient.
Depending on what test you are talking about...
Hardness can be tested by a device that divots the metal with a calibrated point and measures the force required to make a certain depth divot. Also it can be roughly tested by a set of files that have varying hardness. If the file cuts the steel, its harder than the steel.
Structure testing (checking for cracks) can be done by a process called "Magnaflux" which creates a magnetic field in the piece, and filings are sprinkled on it. The filings will indicate the place where the crack is, because the crack makes opposing poles of magnetism in the piece. Another way is called "Dye Penetrant" in which a fluorescent dye is introduced to the surface of the metal and allowed to penetrate the cracks. The rest is washed off with a solvent, which can't remove the dye in the cracks, which show up under black light.
There are literally thousands of tests that can be carried out on a piece of steel, so its hard to answer this generic question, but those are the two most common practical tests I can think of.
Who were the first users of the Internet?
Probably one or two of these guys (you actually need at least two people!):
1. Bob Taylor, one of the original creators of the concept in 1962-1968. He had some sort of internet system between three offices.
Or
2. Lawrence G. Roberts, born 1937 in Connecticut, and who received the Draper Prize in 2001 "for the development of the Internet"
3. Leonard Kleinrock,
4. Robert Kahn,
5. Vinton Cerf.
These last four worked together and developed the 'internet concept' between themselves.
i.e. Larry Roberts and his team created the ARPANet, which was the first significant implementation of Leonard Kleinrock's theories on packet switching, a fundamental feature of (a) the modern internet and (b) ARPANet, the first large network form of the internet.
The Advanced Research Projects Agency Network (ARPANET) developed by ARPA of the U.S. Department of Defense was the world's first operational packet switching network, and the progenitor of the global Internet. During the 1950s, several communications researchers realized that there was a need to allow general communication between users of various computers and communications networks. This led to research into decentralized networks, queuing theory, and packet switching. The subsequent creation of ARPANET in the United States in turn catalyzed a wave of technical developments that made it the basis for the development of the Internet. The first TCP/IP wide area network was operational in 1984 when the United States' National Science Foundation (NSF) constructed a university network backbone that would later become the NSFNet. It was then followed by the opening of the network to commercial interests in 1995. Important separate networks that have successfully entered the Internet include Usenet, Bitnet and the various commercial and educational X.25 networks such as Compuserve and JANET. The collective network gained a public face in the 1990s. In August 1991 CERN in Switzerland publicized the new World Wide Web project, two years after Tim Berners-Lee had begun creating HTML, HTTP and the first few web pages at CERN in Switzerland. In 1993 the Mosaic web browser version 1.0 was released, and by late 1994 there was growing public interest in the previously academic/technical Internet. By 1996 the word "Internet" was common public currency, but it referred almost entirely to the World Wide Web. Meanwhile, over the course of the decade, the Internet successfully accommodated the majority of previously existing public computer networks (although some networks such as FidoNet have remained separate). This growth is often attributed to the lack of central administration, which allows organic growth of the network, as well as the non-proprietary nature of the Internet protocols, which encourages vendor interoperability and prevents any one company from exerting too much control over the network. The IEEE has assigned the 802.1 label to the internetworking among 802 LANs, MANs and other wide area networks, now known as the Internet.
What are the review theory of rain alarm project?
you just have to make a circuit and keep it open.. by not joining the switch wires now when the wires or any other conducting material will get dipped in water the alarm. light, or any other form of signal will be seen..as the circuit will be completed
How you can create an object of a class in java?
for creating objects use the new operator along with a call to the constructor. for ex Triangle t = new Triangle(); In this statement the new operator creates a triangle object and the constructor is called which initializes the object and then new returns a reference of the object which is stored in the reference var "t" of type Triangle.