The Dow Jones Industrial Average (INDEX: ^DJI) followed European markets yesterday and slid down 0.78%. Today, a multitude of earnings -- including those from Apple -- along with a few housing reports could push the market one way or the other. Here's a brief on what to expect.

A trio of Dow earnings
Dow components 3M (NYSE: MMM), AT&T (NYSE: T), and United Technologies (NYSE: UTX) will all release earnings today before the market opens. Analysts expect 3M, which has paid consecutive dividends over 95 years, and raised its annual dividend for 54 consecutive years, to earn $1.48 per share.

The market expects AT&T to report earnings in line with last year. This quarter, AT&T pushed the release of Nokia's Lumia 900, which exacts $100 less of a subsidy from the carrier than the iPhone 4S. A greater proportion of Lumias could help AT&T's margins in the future.

United Technologies hopes to soon close its $16.5 billion acquisition of Goodrich (NYSE: GR); however, the European Commission has until Aug. 9 to decide whether to approve the deal that would give United Technologies a dominant market share in AC power generation. Analysts are expecting its earnings to improve over 5% this quarter from last year's.

And the largest company in the world
Apple will also deliver earnings today, in a quarter where the new iPad was released, along with the iPhone 4S in China. As Bloomberg notes, Apple gained more than an IBM-worth of market value, or $250 billion, over four months. This earnings report will help investors judge whether this run-up was justified. Concerns around Apple include supply shortages of mobile chips, to Verizon's noting iPhone sales of only 3.2 million this quarter compared with 4.3 million last quarter, when the phone was released. However, the median price target for Apple sits at $700 per share, meaning several analysts still see a large upside to the stock.

Housing's continuous recovery
Also today, the Case-Shiller Index for February and new-home sales for March will give investors clues to any hint of a housing recovery. The Case-Shiller 20-city Index, which measures home prices in 20 cities, fell 3.8% in January, and the market expects another decline of 3.4%. We are now seeing home prices around levels last seen in 2003:

Case-Shiller HPI: Composite 20 Chart

Case-Shiller HPI: Composite 20 data by YCharts

New-home sales are expected to increase slightly from February's 313,000 to 318,000 for March. Despite these less than bullish numbers, many professionals are now betting on a housing recovery, following Buffett's words that for new families, "living with in-laws can quickly lose its allure."

Europe's hiccups
Yesterday, European markets fell on news that the eurozone purchasing managers index, or PMI, fell to 47.4 in April, down from 49.1 in March. Any number below 50 signifies an economic contraction, whereas above 50 signals expansion. Along with this, France's electorate showed strong support for the opposition, which favors more spending, and the resignation of the Dutch prime minister around budget talks helped remove the bottom from markets. As Europe sorts out its issues, it will continue to affect markets worldwide.

Prepare for the rest of earnings season
There will be plenty more earnings reports later in the week from other Dow components: tomorrow, it's Boeing and Caterpillar; Thursday, ExxonMobil; and Friday, CVS, Merck, and Procter & Gamble.

Stocks can jump or fall on any tidbit of news, but over the long term it's the underlying business in which you invest and that drives solid long-term returns. Earnings reports are a great peek into how a business is performing, as well as how it might deliver over several years. To make the most of this round of earnings, check out our free report, "5 Stocks Investors Need to Watch This Earnings Season."