Business grinding to a halt for daily prayers is not unusual in conservative Saudi Arabia, but until recently it was rare in the Egyptian capital, especially in affluent commercial districts like Mohandiseen, where the mall is located.

But nearly the entire three-story mall is made up of computer stores run by Salafis, an ultraconservative Islamic movement that has grown dramatically across the Middle East in recent years.

"We all pray together," said Yasser Mandi, a salesman at the Nour el-Hoda computer store. "When we know someone who is good and prays, we invite them to open a shop here in this mall." Even the name of Mandi's store is religious, meaning "Light of Guidance."

Critics worry that the rise of Salafists in Egypt, as well as in other Arab countries such as Jordan and Lebanon, will crowd out the more liberal and tolerant version of Islam long practiced there. They also warn that the doctrine is only a few shades away from that of violent groups like al-Qaeda — that it effectively preaches "Yes to jihad, just not now."

In the broad spectrum of Islamic thought, Salafism is on the extreme conservative end. Saudi Arabia's puritanical Wahhabi interpretation is considered its forerunner, and Saudi preachers on satellite TV and the Internet have been key to its Salafism's spread.

Salafist groups are gaining in numbers and influence across the Middle East. In Jordan, a Salafist was chosen as head of the old-guard opposition group, the Muslim Brotherhood. In Kuwait, Salafists were elected to parliament and are leading the resistance to any change they believe threatens traditional Islamic values.

The gains for Salafists are part of a trend of turning back to conservatism and religion after nationalism and democratic reform failed to fulfill promises to improve people's lives. Egypt has been at the forefront of change in both directions, toward liberalization in the 1950s and '60s and back to conservatism more recently.

The growth of Salafism is visible in dress. In many parts of Cairo women wear the "niqab," a veil which shows at most the eyes rather than the "hijab" scarf that merely covers the hair. The men grow their beards long and often shave off mustaches, a style said to imitate the Prophet Muhammad.

The word "salafi" in Arabic means "ancestor," harking back to a supposedly purer form of Islam said to have been practiced by Muhammad and his companions in the 7th century. Salafism preaches strict segregation of the sexes and resists any innovation in religion or adoption of Western ways seen as immoral.

"When you are filled with stress and uncertainty, black and white is very good, it's very easy to manage," said Selma Cook, an Australian convert to Islam who for more than a decade described herself as a Salafi.

"They want to make sure everything is authentic," said Cook, who has moved away from Salafist thought but still works for Hoda, a Cairo-based Salafi satellite channel.

In most of the region, Salafism has been a purely social movement calling for an ultraconservative lifestyle. Most Salafis shun politics — in fact, many argue that Islamic parties like the Muslim Brotherhood and the Palestinians' Hamas are too willing to compromise their religion for political gain.

Its preachers often glorify martyrdom and jihad — or holy war — but always with the caveat that Muslims should not launch jihad until their leaders call for it. The idea is that the decision to overturn the political order is up to God, not the average citizen.

But critics warn that Salafis could easily slide into violence. In North Africa, some already have — the Algerian Salafi Group for Call and Combat has allied itself with al-Qaeda and is blamed for bombings and other attacks. Small pockets of Salafis in northern Lebanon and Gaza have also taken up weapons and formed jihadi-style groups.

"I am afraid that this Salafism may be transferred to be a jihadi Salafism, especially with the current hard socio-economic conditions in Egypt," says Khalil El-Anani, a visiting scholar at Washington's Brookings Institution.

The Salafi way contrasts with the Islam long practiced in Egypt. Here the population is religious but with a relatively liberal slant. Traditionally, Egyptian men and women mix rather freely and Islamic doctrine has been influenced by local, traditional practices and an easygoing attitude to moral foibles.

But Salafism has proved highly adaptable, appealing to Egypt's wealthy businessmen, the middle class and even the urban poor — cutting across class in an otherwise rigidly hierarchical society.

In Cairo's wealthy enclaves of Maadi and Nasr City, robed, upper-class Salafis drive BMWs to their engineering firms, while their wives stay inside large homes surrounded by servants and children.

Sara Soliman and her businessman husband, Ahmed el-Shafei, both received the best education Egypt had to offer, first at a German-run school, then at the elite American University in Cairo. But they have now chosen the Salafi path.

"We were losing our identity. Our identity is Islamic," 27-year-old Soliman said from behind an all-covering black niqab as she sat with her husband in a Maadi restaurant.

"In our (social) class, none of us are brought up to be strongly practicing," added el-Shafei, also 27, in American-accented English, a legacy of a U.S. boyhood. Now, he and his wife said, they live Islam as "a whole way of life," rather than just a set of obligations such as daily prayers and fasting during the holy month of Ramadan.

A dozen satellite TV channels, most Saudi-funded, are perhaps Salafism's most effective vehicle. They feature conservative preachers, call-in advice shows and discussion programs on proper Islamic behavior.

Cairo's many Salafist mosques are packed on Fridays. Outside Shaeriyah mosque, a bookstall featured dozens of cassettes by Mohammed Hasaan, a prolific conservative preacher who sermonizes on the necessity of jihad and the injustices inflicted on Muslims.

Alongside the cassettes, a book titled "The Sinful Behaviors of Women" displayed lipstick, playing cards, perfumes and cellphones on the cover. Another was titled "The Excesses of American Hubris."

Critics of Salafism say it has spread so quickly in part because the Egyptian and Saudi governments encouraged it as an apolitical, nonviolent alternative to hard-line jihadi groups.

These critics warn that the governments are playing with fire — that Salafism creates an environment that breeds extremism. al-Qaeda continues to try to draw Salafists into jihad, and its No. 2, the Egyptian Ayman al-Zawahri, praised Salafists in an Internet statement in April, urging them to take up arms.

"The Salafi line is not that jihad is not a good thing, it is just not a good thing right now," said Richard Gauvain, a lecturer in comparative religion at the American University in Cairo.

The Salafis' talk of eventual jihad focuses on fighting Americans in Afghanistan and Iraq, not on overthrowing pro-U.S. Arab governments denounced by al-Qaeda. Most Salafi clerics preach loyalty to their countries' rulers and some sharply denounce al-Qaeda.

Egypt, with Saudi help, sought to rehabilitate jailed Islamic militants, in part by providing them with Salafi books. Critics say President Hosni Mubarak's government sees the Salafists as a counterweight to the opposition Muslim Brotherhood.

The political quietism of the Salafis and their injunctions to always obey the ruler are too good an opportunity for established Arab rulers to pass up, said novelist Alaa Aswani, one of the most prominent critics of rising conservatism in Egypt.

"That was a kind of Christmas present for the dictators because now they can rule with both the army and the religion," he said.

The new wave of conservatism is not inevitable, Aswani maintains, noting that his books — including his most popular, "The Yacoubian Building" — have risquDe themes and condemnations of conservatives, and yet are best-sellers in Egypt.

"The battle is not over, because Egypt is too big to be fitting in this very, very little, very small vision of a religion," he said.