In a world where one line of data can mean the difference between success or ruin for individuals, companies, or even entire countries, the validity and security of sensitive data has increasingly become of paramount concern. A raft of cyber-security companies are answering these important issues with solutions for everything from email privacy to network breach protection. One such company, and a stand out in its field, is Computer Sciences Corp. (CSC).

Internet search behemoth Google (GOOG) is looking for ways to help ward off cyberattacks, and it appears that they have turned to the National Security Agency (NSA).

According to the Washington Post, an agreement between the two is being finalized. The agreement would help Google with its recent "corporate espionage attack" that it believes originated in China. This attack targeted the company's computer networks. The alliance would help Google, and its users, from any future attacks.

The Wall Street Journal (subscription required) reports that the FBI is looking into a potential computer-security breach that resulted in the theft of tens of millions of dollars from Citibank by computer hackers.

These hackers appear to be linked to a Russian cyber gang who targeted Citigroup's (C) Citibank subsidiary, including its North American retail bank and other businesses. This attack was detected over the summer, but there is a chance that it could have happened as much as a year earlier.

Every day, there seems to be a headline about some type of online security breach. Just look at the recent denial-of-service attacks at Twitter and Facebook. Yes, it seems that no one is immune from the perils of the electronic world.

Interestingly enough, this is good news for ArcSight (NASDAQ: ARST), which develops a variety of security solutions. To get a sense of this, look at the company's fiscal Q1 results (which came out Thursday).

With President Obama highlighting the national importance of cyber security, we turn to technology specialist Gregg Early to find the best investment ideas in the sector.

Noting that "cyber security is one of the biggest new sectors in the information technology industry," the editor of Personal Finance offers a trio of buys in the field -- McAfee (NYSE: MFE), Versar (AMEX: VSR), and Unisys (NYSE: UIS).

The advisor explains, "In exchange for an annual fee, McAfee allows users to download the basic security software and regular updates. These frequent updates are essential because virus and malware threats are constantly evolving.

The Washington Post reported over the weekend that the CIA had warned U.S. utilities of the possibility of attacks, or threats with extortion demands, via the internet. At a conference in New Orleans attended by security officials from governments, utilities, and companies such as Chevron Corp. (NYSE: CVX) and BP (NYSE: BP), a cybersecurity analyst broke with CIA disclosure polices to detail several recent cyber intrusions outside the United States, one case resulting in a power outage that affected several cities.

Increasingly sophisticated intrusions into corporate computer systems have cost companies worldwide more than $20 billion each year, according to some estimates. And extortion is a growing threat, with attackers radically increasing their take from online gambling sites, e-commerce sites, and banks, which pay up to prevent their sites from being shut down and to avoid public knowledge their sites have been hacked.

With the rising tide of cyber attacks on the infrastructure over the past year or so, and the vulnerability of the power grid, transportation systems, and big banks becoming increasingly clear, investors have to wonder how secure the exchanges are from extortion or efforts to manipulate the markets by individuals or organized groups. The London Stock Exchange suffered a cyber attack this past June. Such attacks frequently originate from overseas, sometimes supported by foreign governments, and perpetrators can be next to impossible to track down and bring to justice.