The market in general eased down today, with the S&P 500 closing down 0.20%. However, the Nasdaq (^IXIC -0.64%) ended the day up 0.20%, thanks in large part to outsized gains from Apple (AAPL 0.52%). Let's look at some of the day's biggest winners in tech.

Today's featured winners

Company Price Change
Apple 3.15%
3D Systems (DDD -1.15%) 11.52%
Facebook (META -10.56%) 8.09%

Each of the stocks has continuing storylines that contributed to today's gains.

Apple
Apple shares sank as low as $505.75 on Nov. 16 but have rallied 17% since bottoming out that day. There are a number of reasons for Apple's surge, but a common theme continues to be upgrades out of Wall Street. At $505.75, the company traded at just over 11 times earnings. While Apple's growth is slowing, that's a very low multiple relative to the opportunities still in front of the company.

Today saw another "buy" rating slapped on Apple, this time compliments of Citi. However, more noteworthy news surrounding the company could be focused on Black Friday shopping. Not only did the iPad dominate Black Friday online shopping -- it was the most used mobile device among online shoppers -- but reports from Apple analyst Gene Munster also noted that retail traffic at Apple stores was markedly higher this year.

With supply constraints clearing up in time for the holidays, Apple looks poised to surpass expectations, which had been dropping in recent months.

3D Systems
The 3-D printer company saw its shares surge 11.5% today. The company had faced scrutiny over its accounting of organic versus acquired growth, but it held a conference call last Monday to dispute certain claims against the company. Days before the call, fellow Fool Jim Mueller had laid out a case that bearish articles against the company were mistaken in their claims that 3D Systems was obfuscating organic growth.Today's rally also coincides with the introduction of two printers, the ProJect 3500 HDMax and ProJet 3500 CPXMaxprofessional.

The new printers, though, probably don't explain 3D Systems' rally on their own. Instead, the market could be taking stock of the company's future after light trading last week around Thanksgiving. It should also be noted that rival Stratasys (SSYS -1.11%) also rallied 7.3% today, so there was optimism for 3-D printing in general.

Facebook
Finally, we come to Facebook, which saw its shares surge more than 8%. The company has been on a heady rally the past couple of weeks, having risen 35% from its Nov. 9 closing price. There are multiple catalysts investors could point to for recent gains.

For one, Facebook didn't sell off after a large lockup on its shares expired on Nov. 14. The company has traded highly on momentum since going public, so a rally after an event most investors were expecting selling from can often build on itself.

Then there's Wall Street. Facebook has been seeing more optimism from the analyst community following its last earnings, when it announced surprising strength in mobile advertising. Today, Facebook saw another upgrade, this time receiving a $33 price target and buy rating from Bernstein research.

Finally, Facebook has been looking to continue expanding its revenue sources. Today's Bernstein upgrade was driven in large part by optimism over its Ad Exchange platform, which allows retargeting of ads, which can command higher rates than conventional display ads.