Today, the Dow Jones Industrial Average (INDEX: ^DJI) closed at 13,494, up just more than 12 points, or 0.1%. Both the S&P 500 and Nasdaq also closed up, by 0.36% and 0.49%, respectively. Although the Dow closed just slightly higher, it charted a fairly nice bell curve today -- down in the opening hour, moving upward to peak at midday, and then falling back to the breakeven point for the past few hours before a slight uptick 30 minutes before the closing bell.

Why the Dow moved today
There were a number of causes for the Dow's moves today, but I'd like to point out three in particular.

First the ADP jobs report, which was released this morning, indicated that U.S. private-sector jobs increased by 162,000 in September. Although these numbers look great, the ADP report seems to be flawed. The reports issued by the U.S. Department of Labor often widely vary from what ADP publishes. The Labor Department will release its report on Friday.

Another event that moved the Dow was Hewlett-Packard's (NYSE: HPQ) meeting with analysts. HP CEO Meg Whitman made it clear she understands that the company is not in an ideal place financially. She also stated that the turnaround will take longer than she would like. The final blow came after the company issued 2013 guidance that was much lower than what most were expecting. Hewlett-Packard closed the day down 13%.

Chipmaker Intel (Nasdaq: INTC ) also ended the day lower, down 1.27%. The fall started in the second half of the day, shortly after HP's slide began. Intel's chips are used in about 80% of PCs; therefore, when the CEO of one of the world's largest PC makers issues lower guidance and expresses concerns of a long, slow recovery, these shares are going to get hit.

The third market mover was the U.S. Energy Information Administration's weekly Petroleum Status Report. While the report stated that inventories were lower by 500,000 barrels from the previous week, it also contained indications that oil demand is slowing. Over the past four weeks, motor gasoline supplies average 8.7 million barrels a day, representing a 2.5% decrease from the same period last year. Distillate fuel is also down, seeing a 4.5% decrease from the same period last year. On the news, Chevron (NYSE: CVX) closed the day down 1.55%, while ExxonMobil (NYSE: XOM) ended lower by just 0.02%.

These events and many more moved the Dow today, and while the presidential debate tonight may have an effect on the markets tomorrow, the election undoubtedly will. To find out which stocks will be affected depending on who wins,  grab our free article. Don't wait; the elections are just around the corner, so click here.