The computer virus that blackmail you

t's a malicious virus that locks the user out of their computer and demands a fee to return their files.

A report published by the Australian government claims 72% of businesses surveyed experienced ransomware incidents in 2015.

The figure was just 17% in 2013 .

It's also a growing threat for mobile devices as it can be hidden in an app, says Gert-Jan Schenk, vice-president at internet security company Lookout.

"For the most part, we've seen ransomware delivered through drive-by downloads - it pretends to be a popular app, increasing the chances that you'll click on it," he explains.

"To avoid these threats, users should be very careful about what apps they install, and where they come from - read the reviews on Google Play, and avoid side-loading from untrusted sources."

How does it work?

Image copyrightThinkstock

Image caption

Like most computer viruses, ransomware often arrives in the form of a phishing email, or spam, or a fake software update - and the recipient clicks a link or opens an attachment.

The virus then sets to work encrypting the user's files.

Once the computer is effectively locked down, it demands a fee - often in bitcoins because it is less easy to trace - for the return of the files.

The fee is generally one or two bitcoins - the equivalent of about $500 (£330).

It is less common now, but in the earlier days of the malware - about five years ago - the ransom note could take the form of a law enforcement notice.

The user was directed to a web page that appeared to be from, for example, the FBI, falsely claiming illegal images of children had been been found on the machine and a fine was payable.

There is generally a time limit to comply, after which the ransom increases.The

Is there any way to get round it?

Image copyrightThinkstock

Image captionBack up, back up, back up...

Sometimes it is just a threat, but mostly the virus really does encrypt files.

The only way to retrieve your files without paying the ransom is to go to a backed-up version.

Neil Douglas, from Edinburgh-based IT company Network Roi, has just helped a small business client whose server was hit by ransomware.

"We had to recover everything from back-up. We'd had a back-up two minutes before the infection, so the timing couldn't have been any better - but it did result in quite a bit of downtime," he says.

"You could risk paying them - but it's a bit like paying a blackmailer. We would only recommend it as a last resort.

"You don't know whether they'll come back for more, you don't know that they'll clear the infection."

Cybersecurity expert Prof Alan Woodward says paying also leaves you vulnerable to further cybercrime.

"As soon as you pay up, you get on a suckers' list and you'll probably get contacted again," he says.

"It's low-hanging fruit for the criminals." ransom is usually demanded in the form of bitcoins

Can you run your computer without operating system?

Yes. But you have a lot of work to do. Without an operating system using and enforcing a standard, systematic approach to running the computer, you're put in the position of writing code (or programs) that must tell the computer exactly what to do. So if you want to type up a document in a word processing program, you'd have to create from scratch code that tells your computer to respond to each character pressed on your keyboard. Then you'd have to write a code that told the computer how those responses must translate to a screen. You'd have to tell your computer how to draw the character you want! Think of every single option or possibility your word processing program has. You'd have to write code for every single one of those directly onto your hard drive.

Let's go back to our general contractor analogy. If we're building a house, we'll want it to have certain features like plumbing, electrical work and windows. In a computer, we also want features like a program that creates documents, one that accesses the Internet and one that stores our photos. Without an operating system, it's not just that your "carpenter" doesn't know where to hammer in nails to a beam to get the room you want -- it's also that you have to forge the hammers, and you have to create the nails.

An operating system provides a uniform set of screws, lumber and any other material you need. It can go back and forth between rooms so fast you didn't even know it left the one you were in.

And that's really important, because here's another thing: Remember how we were talking about the operating system only being able to concentrate on one thing at a time? Well, without one, your computer could run one program. Period. You could create a document. You could save it. You could print it. But you couldn't look at that document and keep a clock running on your desktop. If you don't have an operating system, you're stuck doing one -- and only one -- process at a time.

What is operating system?

OPERATING SYSTEM:

The operating system is the most important program that runs on acomputer. Every general-purpose computer must have an operating system to run other programs and applications. Operating systems perform basic tasks, such as recognizing inputfrom the keyboard, sending output to the display screen, keeping track of files and directories on the disk, and controlling peripheral devices such as disk drives and printers.

For large systems, the operating system has even greater responsibilities and powers. It is like a traffic cop -- it makes sure that different programs and users running at the same time do not interfere with each other. The operating system is also responsible for security, ensuring that unauthorized users do not access the system.

The Classification of Operating systems

Multi-user: Allows two or more users to run programs at the same time. Some operating systems permit hundreds or even thousands of concurrent users.

Multiprocessing : Supports running a program on more than one CPU.

Multitasking : Allows more than one program to run concurrently.

Multithreading : Allows different parts of a single program to run concurrently.

Real time: Responds to input instantly. General-purpose operating systems, such as DOS and UNIX, are not real-time.

Operating systems provide a software platform on top of which other programs, called application programs, can run. The application programs must be written to run on top of a particular operating system. Your choice of operating system, therefore, determines to a great extent the applications you can run. For PCs, the most popular operating systems are DOS, OS/2, and Windows, but others are available, such as Linux.

Ada (Founder of scientific computing)

Born: London, England, December 10, 1815

Died: London, England, November 27, 1852

Analyst, Metaphysician, and Founder of Scientific Computing

Ada Byron was the daughter of a brief marriage between the Romantic poet Lord Byron and Anne Isabelle Milbanke, who separated from Byron just a month after Ada was born. Four months later, Byron left England forever. Ada never met her father (who died in Greece in 1823) and was raised by her mother, Lady Byron. Her life was an apotheosis of struggle between emotion and reason, subjectivism and objectivism, poetics and mathematics, ill health and bursts of energy.

Lady Byron wished her daughter to be unlike her poetical father, and she saw to it that Ada received tutoring in mathematics and music, as disciplines to counter dangerous poetic tendencies. But Ada's complex inheritance became apparent as early as 1828, when she produced the design for a flying machine. It was mathematics that gave her life its wings.

Lady Byron and Ada moved in an elite London society, one in which gentlemen not members of the clergy or occupied with politics or the affairs of a regiment were quite likely to spend their time and fortunes pursuing botany, geology, or astronomy. In the early nineteenth century there were no "professional" scientists (indeed, the word "scientist" was only coined by William Whewell in 1836)--but the participation of noblewomen in intellectual pursuits was not widely encouraged.

One of the gentlemanly scientists of the era was to become Ada's lifelong friend. Charles Babbage, Lucasian professor of mathematics at Cambridge, was known as the inventor of the Difference Engine, an elaborate calculating machine that operated by the method of finite differences. Ada met Babbage in 1833, when she was just 17, and they began a voluminous correspondence on the topics of mathematics, logic, and ultimately all subjects.

In 1835, Ada married William King, ten years her senior, and when King inherited a noble title in 1838, they became the Earl and Countess of Lovelace. Ada had three children. The family and its fortunes were very much directed by Lady Byron, whose domineering was rarely opposed by King.

Babbage had made plans in 1834 for a new kind of calculating machine (although the Difference Engine was not finished), an Analytical Engine. His Parliamentary sponsors refused to support a second machine with the first unfinished, but Babbage found sympathy for his new project abroad. In 1842, an Italian mathematician, Louis Menebrea, published a memoir in French on the subject of the Analytical Engine. Babbage enlisted Ada as translator for the memoir, and during a nine-month period in 1842-43, she worked feverishly on the article and a set of Notes she appended to it. These are the source of her enduring fame.

Ada called herself "an Analyst (& Metaphysician)," and the combination was put to use in the Notes. She understood the plans for the device as well as Babbage but was better at articulating its promise. She rightly saw it as what we would call a general-purpose computer. It was suited for "developping [sic] and tabulating any function whatever. . . the engine [is] the material expression of any indefinite function of any degree of generality and complexity." Her Notes anticipate future developments, including computer-generated music.

Ada died of cancer in 1852, at the age of 37, and was buried beside the father she never knew. Her contributions to science were resurrected only recently, but many new biographies* attest to the fascination of Babbage's "Enchantress of Numbers."

Do you have any idea about father of computer?

Charles Babbage - The Father of Computers

WHO invented the first computer? And when?

    The answer will surprise you: it was Charles Babbage, in the year 1832.
    Babbage, who was born in London in 1791, was a great mathematical genius. He was a natural inventor, and invented all sorts of new products.
    When he finished school, he went to study mathematics at Cambridge University. Later, he got a job teaching at the university ; and while Professor of Mathematics in this illustrious university, he designed his "first difference engine". This was, basically, a hand-operated mechanical calculator.
    He took nine years to build a part of the machine. This machine, which is in the London Science Museum, can make complex mathematical calculations. It is a basic mechanical computer.
    Babbage dreamed however of more complicated machines. In fact, he did not only dream; he began to design them. The result was a series of "analytical engines" which were in fact powerful computers!
    His designs contained processors (he called them "mills"), control units, a memory (he called it a store), and an input/output system. These are the four essential parts of a modern mathematical computer!
    Alas, Babbage was born 100 years too soon! His "second difference engine" could not use electricity, since this had not yet become a usable source of power; so Babbage had to make do with mechanical systems. For this reason, the machine was big and very complicated, and very expensive. Though Babbage produced complete plans for the machine, he could not build it. It was too sophisticated for its age!

    It was not until almost 160 years later that Babbage's "second difference engine" was finally manufactured. The first working version of this machine was built by the Science Museum in London, for the Babbagebicentenary in 1991. It can now be seen at the  Museum; a second machine was then built for an American high-tech millionnaire, who put it in the Computer History Museum, in Mountain View, California.
           Babbage's analytical engines would have used "programmes" like those used in the textile industry to make complicated patterns; but they were never built. This brilliant mathematician really was too far ahead of his time !

Why memory is needed ?

Memory is needed to store data and retrieve it when needed. Computers have two kind of memory, one is primary and another is secondary.
Secondary memory is commonly known as just storage. It's used to store files when they are not needed by the processors. The examples are HDD, SSD, USB Drives, SD Cards etc.

Primary memory is needed to execute any program. Your program when executed loads itself into primary memory. When program runs, it needs to work on variables, objects, data structure etc. to store data. For example if it needs to store value 10, it'll need an integer datatype while for storing text, it'll need a string data type. These data types stores these values into primary memory. Apart from that some programs needs to access files which are also gets loaded into primary memory for execution and then after releasing them, they go back with changes (if any) to secondary memory.

Primary memory example could be RAM, ROM, L1 & L2 Cache, Registers etc. Processor works as a primary memory too since they have limited storage too.

Now the question is why do we need Primary memory like RAM at all? Can't we just use Secondary memory for this?
We can, in fact we do. When RAM ran out of space to open new files, the OS uses Hard disks as primary memory by creating page files on that. If you have seen pageswap or page files in your system's hidden files then you have seen the proof.
Now why do we need it? We need processors to run the commands, however processors are really costly and they can not hold much data in them. Processors are really fast, but we need to store the data processors are not currently using, even in the running program. Caches are faster kind of memory which can be used by Processors very easily. However they are costly too (L1 is faster and costly than L2). Registers are next faster memory and RAM is the next fastest and the cheapest option.
RAMs can't hold the data, so we need a persistent data storage such as HDDs. HDD works on magnetic resonance principles and are really slow. However they are faster than Optical disks such as CDs and DVDs. SSDs are faster, but they still can't compete with RAMs. RAMs are electronic drives which can connect with Processors with ease.

Consider an example of slow moving traffic. If the fastest car is behind slow moving cars, it will move as fast as the slowest car in the lane. That's why the slowness of HDDs affect the Processors' execution speed. Thus we need RAM for this.

"Difference between human viruses and computer viruses"

Biological Viruses (or Human Viruses) are Nanotechnology by Nature while computer viruses are infectious agent by made by humans. Most often the people think Biological viruses and Computer viruses as a same entity, although both cause infection and damage to their host (or target) and some of their features & characteristics are same but they are quite different from each other. Following table enlists some interesting main difference between Biological Virus and Computer Viruses.

There are some differences i'm going to explain:

1. Living – non living:

Biological VirusBiological viruses are living (at least to some extent) biological entity who can reproduce itself

Computer VirusComputer viruses are non – living at all, they are manmade malicious computer coding which are programmed to perform specific functions

2. Host:

Biological VirusThey are living, thus infects living things. Biological Viruses can infect all form of life including Human, Animals, Plants, Insects, Bacteria, Protozoa, Fungi, Archae and other viruses (Yes, there are some viriophage exist)

Computer VirusThey are programmed, thus made impact on programs (softwares) Computer viruses infect mostly PCs, Servers, websites and software. Computer viruses mostly targets PCs with MS windows Operating system and rarely other Operating System.

3. History:

Biological VirusThe history of Biological virus’s evolution is dated back where the Life begins; they are as old as bacteria (about 2.5 billion year). The first written and proven case of viral infection is depicted on 3700 B.C old ancient painting which shows the case of poliomyelitis.

Computer VirusThe first computer virus was “Creepy” virus which is written (coded) in 1971 by Bob Thomas. This virus remotely spread and copied itself, just show the message “I am creepy, catch me if you can”.

4. Components:

Biological VirusAs a biological entity or living organism, Biological virus contain genetic material (in the form of RNA or DNA), covered by a coat of protein (called Capsid) and sometime by a lipid Envelop

Computer VirusA computer virus is not more than a few lines of code. It contains a script or code of programming language written in C, C++ or other assembly languages.

5. Mechanism of action:

Biological VirusBiological viruses infect their host after they enter the host body and reach inside the cell where the virus uses the host genetic material (DNA or RNA )to replicate and expend their population

Computer VirusComputer viruses, similarly infect computers when they enter and reach the registry (or the specific components/area for which they are programmed) where they cause the damage (usually hiding or disabling some files or functions) .

6. Types:

Biological VirusClassify by many ways, mostly by the body system which the biological virus infect. Their types include Neuroviruses, Enteroviruses, Rhino viruses, Respiratory viruses, etc.

Structurally their classification include RNA viruses and DNA viruses

Computer VirusClassify by the components or subsystem of the host which they infects. Their types includes, system viruses, Macro viruses (infect application e.g.MS Word, MS Outlook) and Boot sector viruses (which target Master Boot Record).

Programmatically their types include .exe viruses, .COM viruses or  a batch files (.bat) virus.

7. Hazards:

Biological VirusThey causes severe damage to the organ or system they involved which may be reversible (as in case of Hepatitis A, Flu) or lifelong irreversible (i.e. Poliomyelitis, Rabies or Hepatitis C viruses)

Computer VirusThey causes damage to the system or component of the PC which they infect and can result in burden on system memory, system crush and permanent lost of a document or a file or other data.

8. Benefits:

Biological VirusBiological viruses to some extent, are helpful and beneficial in the sense that they are being used in gene therapy to introduce therapeutic genetic material to the diseased cell (e.g. in case of cancer)

Computer VirusComputer viruses, till to date, has no any beneficial role. They always cause damage and lost to the system am data.

9. Prevention:

Biological VirusBiological viruses are preventable by getting vaccinated against them. Vaccines (or even some viruses) help our boy to develop immunity against the occurrence or re-occurrence of the same disease again.

Computer VirusWell, there is no such scenario in case of computer viruses, even with having a powerful Antivirus or fire wall on your system, your system may still got infected, as the developer continually write the malicious code and it across networks to get their job done.

10. Treatment:

Biological VirusBiological viruses can be treated to some extent with Antiviral drugs e.g. Acyclovir or you can get symptomatic treatment against them.

Computer VirusComputer viruses can be detect and remove with the help of Antivirus. But still it is unpredictable how much damage they can left or made to the system and some time you need to re-install the operating system