Computer crime refers to criminal activity involving a computer. The computer may be used in the commission of a crime or it may be the target. Net-crime refers to criminal use of the Internet. Cyber-crimes are essentially a combination of these two elements and can be best defined as "Offences that are committed against individuals or groups of individuals with a criminal motive to intentionally harm the reputation of the victim or cause physical or mental harm to the victim directly or indirectly using modern telecommunication networks such as the Internet (Chat rooms, emails, notice boards and groups) and mobile phones (SMS/MMS)". 
In its most simple form, cyber-crime can be defined as any illegal activity that uses a computer as its primary means of function. The U.S. Department of Justice broadens this definition to include any illegal activity that uses a computer for the storage of evidence. The term 'cyber-crime' can refer to offenses including criminal activity against data, infringement of content and copyright, fraud, unauthorized access, child pornography and cyber-stalking.
The United Nations Manual on the Prevention and Control of Computer Related Crime includes fraud, forgery and unauthorized access in its definition of cyber-crime. Cyber-crime in effect covers a wide range of attacks on individuals and organisations alike. These crimes may include anything from an individual's emotional or financial state to a nation's security.
There are two main categories that define the make up of cyber-crimes. Firstly those that target computer networks or devices such as viruses, malware, or denial of service attacks. The second category relate to crimes that are facilitated by computer networks or devices like cyber-stalking, fraud, identity-theft, extortion, phishing (spam) and theft of classified information.
In order to highlight the scale of cyber-crime globally, the Norton Cyber-crime Report 2011 revealed 431 million adults in 24 countries had been victims' of cyber-crime in that year. Computer based crime is escalating at an alarming rate. In the report Norton calculated the financial cost of global cyber-crime at $388 billion. This is more than the combined international market for marijuana, heroin and cocaine, estimated at $288 billion. Assuming its current growth rate continues, cyber-crime will soon surpass the entire global drug trafficking market that is estimated to be worth $411 billion annually.
Cyber-crimes have expanded to include activities that cross international borders and can now be considered a global epidemic. The international legal system ensures cyber criminals are held accountable through the International Criminal Court. Law enforcement agencies are faced with unique challenges and the anonymity of the Internet only complicates the issues. There are problems with gathering evidence, cross-jurisdictional issues and miscommunication related to reporting.
It is widely known that victims of Internet crimes are often reluctant to report an offence to authorities. In some cases the individual or organization may not even be aware a crime has been committed. Even though facilities for reporting incidents of cyber-crime have improved in recent years many victims remain reluctant due essentially to embarrassment.
International cooperation is essential if an effective response is to be found against global cyber-crime. No nation can expect to effectively combat the issue alone. Many computer based crimes are initiated 'off-shore' and this presents enormous challenges to any nations law enforcement agencies. It is critical that agencies from around the world formulate actionable plans to detect, follow, arrest and prosecute cyber criminals.
For example, in the past two years Australia has adopted the National Criminal Intelligence Fusion Capability, a key element of the Commonwealth Organized Crime Strategic Framework (COCSF). This body brings together expertise, data and technology across a range of government and law enforcement agencies and enables international collaboration.
The problem of cyber-crime seems almost immeasurable in size. Looking at recent trends and advances in mobile technology and cloud computing we realize it is an ever-evolving and rapidly changing dynamic. There is growing evidence globally of newly formed partnerships between government and industry aimed at prevention. These partnerships create opportunities to share information and bolster law enforcement response to organized Internet-based crime.
This sharing of information creates concerns in its self. It is an extremely complex and sensitive issue. A balance must be found in efficiently maximizing distribution of information and protecting it from the organized cyber-criminal element.
Cyber-crime covers such a broad scope of criminal enterprise. The examples mentioned above are only a few of the thousands of variants of illegal activities commonly classed as cyber-crimes. Computers and the Internet have improved our lives in many ways, unfortunately criminals now make use of these technologies to the detriment of society.
 Halder, D., & Jaishankar, K. (2011) Cyber crime and the Victimization of Women: Laws, Rights and Regulations. Hershey PA, USA: IGI Global. ISBN: 978-1-60960-830-9