Calling it the "most sweeping economic recovery package in our history," President Obama today signed a $787 billion economic stimulus bill aimed at creating or saving at least 3.5 million jobs and jolting the economy out of its slump.

"We have begun the essential work of keeping the American dream alive in our time, and that's why we're here today," the president said before an audience in Denver, Colorado. "I don't want to pretend that today marks the end of our economic problems, nor does it constitute all of what we're going to have to do to turn our economy around. But today does mark the beginning of the end -- the beginning of what we need to do to create jobs for Americans scrambling in the wake of layoffs."

Obama said that the legislation, while representing only one part of a broader strategy to address the recession, will:

• Provide the largest new investment in the country's infrastructure since the interstate highway system was built in the 1950s, creating nearly 400,000 jobs to revitalize the nation's infrastructure.

• Provide the largest investment in education in the nation's history, building 21st century classrooms and labs, training upcoming math and science teachers, and providing aid to states and localities to prevent teachers from losing their jobs.

• Allow for a $2,500 annual tax credit for higher education expenses.

• Computerize medical records and prevent 7 million individuals from losing their healthcare coverage.

• Lay the groundwork for a "green economy" by doubling the amount of renewable energy over the next three years, providing tax credits and loan guarantees for companies that produce alternative energy products, and creating a "smarter" electric grid. The bill's energy provisions will save taxpayers $1 billion by cutting energy costs in federal buildings by 25 percent, according to the president.

• Provide the largest increase in basic research funding for agencies such as the National Institutes of Health and the National Science Foundation.

• Provide the most progressive tax cuts in history by giving tax breaks to 95 percent of families.

"What I'm signing then is a balanced plan with a mix of tax cuts and investments," Obama said, adding that the legislation is free of pet projects -- called earmarks -- and pork-barrel spending, and will be implemented with an "unprecedented level of transparency and accountability."