(FORTUNE Small Business) – Charity. Philanthropy. Noblesse oblige. Giving back. You can feel the difference. The first three phrases are rooted in old European traditions: wealthy folks, from the privacy of their estates, giving discreetly to help the poor. Charity dates to the 14th century and a Latin word for love; noblesse oblige to the 1830s, shortly before the Communist Manifesto proclaimed that upper-class largesse was not enough. But "give back" feels unmistakably 21st century: cool, pragmatic, transactional. Along with "social entrepreneurship," it's the lingo of a so-called new philanthropy. And it's true. Charity these days has a different look and set of ambitions. People give earlier and oftener, and in ways that are changing society--how we spend money, how we make it. Still, what's "new" isn't always salutary, and in one big way, philanthropy hasn't changed: there still ain't enough of it.

But first: the new. Celebrity patrons of the distant past, like the Renaissance's Medicis, gave money throughout their lives. Andrew Carnegie famously declared that a man who dies rich dies disgraced, and he took care not to. But most givers have followed the Warren Buffett model: charity as an after-death experience. Now a younger generation is giving money away almost as soon as it makes it--or even before. Tycoon Ted Waitt, 37, stopped running Gateway to focus on philanthropy. Magazines feature stories of teens who "make a difference." Parenting experts suggest inculcating the habit of charity with a child's first allowance.

The new givers want more control. Scandals at even the most august charities have illustrated the dangers of unpoliced giving. But this change is also about a culture that's skeptical and unsentimental. Givers sit on boards and demand progress reports. They want results. What kind of results? Philanthropists have always supported things--from settlement houses to symphonies--to make their own communities more humane or graceful. "Community'' today, of course, is global, and so are philanthropic ambitions (world peace, preventing global warming). But givers who hail from the "me" decades often aim at smaller niches, from their own obsessions to their own survival. Paul Allen funded a rock museum insprired by his hero, Jimi Hendrix. Michael J. Fox, struck by Parkinson's, has vowed to "fast-forward the cure."

The most striking change in philanthropy is how it is being woven into everyday life. In the '80s, companies began to find ways to match purchases--of ice cream or spaghetti sauce, for instance--with donations. With the Web, the "shop to give" model is just a click away.

Despite the changes, the new philanthropy has a lot in common with the old. The biggest chunk of money goes to religion, another chunk to a giver's alma mater. Donors still want their name on a plaque, and groups cater to that need at every level. Send money to save the whales, and you get a video of your own cetacean. Unfortunately, what has changed least is how much we give. Despite huge increases in personal and corporate wealth, the total has stayed flat--at 2% of GNP--for 30 years. We hear of donations in big dollars but rarely know how much of someone's wealth it represents. (Note: Small companies give more, suggests a new Conference Board study.) Today's wealthy, says David Brooks in his book Bobos in Paradise, are stuggling to come to terms with their own noblesse oblige. We'll have to wait and see how they define it.