Market capitalization, which is basically the total of all of a company’s shares multiplied by the stock price, is a good indicator as to what companies are the most valuable. Of course, the top 10 companies with the biggest market caps can change at any moment, but, these 10 were leading all others as of Jan. 24, 2013, according to YCharts’ market capitalization rankings. On Friday, Exxon overtook Apple as the world’s most valuable company when its stock gained 38 cents to $91.73 for a market capitalization of $418 billion, the Associated Press reported. It is the first time Exxon has ended up on top since early 2012.

Apple’s stock fell 2.4 percent Friday, but the company still dominates the smartphone market. Investors are looking forward to a rumored Apple TV as well as the next iPhone and iPad.

MARKET CAPITALIZATION: $413 billion

Apple fact: The company sold 47.8 million iPhones in the last quarter, according to a company-issued press release.

High gas prices may be tough for consumers, but they have not hurt Exxon Mobil, which continues to churn out profits for its investors. Considered the biggest investor-owned energy company in the world, Exxon was the most valuable company between 2005 and fall 2011, when it started going back and forth with Apple.

MARKET CAPITALIZATION: $418 billion

Exxon fact: Exxon Mobil recently acquired a 75 percent interest in the Tugela Sotuh Ezploration Right in South Africa, according to a company-issued press release.

China’s biggest oil producer has benefited from the country’s continued manufacturing growth. According to the Associated Press, the company could be seen as the most valuable company in the world if it was based on prices on the isolated Shanghai stock exchange.

MARKET CAPITALIZATION: $263.65 billion

PetroChina fact: In the first three quarters of 2012, crude oil output for PetroChina was 683.2 million barrels, according to the company’s website.

Google has made most of its money through search, but the company is also experimenting with driverless cars.

MARKET CAPITALIZATION: $247.7 billion

Google fact: Google is developing “smart” glasses. A prototype has been worn by co-founder Sergey Brin, according to the Los Angeles Times.

Berkshire Hathaway technically appears on the list twice as its two classes of stock are each big enough to make the list.

MARKET CAPITALIZATION: $241.27 billion (series A stock), $241.15 billion (series B stock)

Berkshire Hathaway fact: Berkshire has bough a number of print newspapers in recent years.

As the economy has tanked Walmart has largely been immune to the downturn as its low-price strategy has resonated with consumers.

MARKET CAPITALIZATION: $234.59 billion

Walmart fact: Walmart has more than 10,900 stores in 27 countries, according to its website.

Microsoft recently released its Windows 8 operating system, which was a major revamp of the popular software.

MARKET CAPITALIZATION: $231.63 billion

Microsoft fact: Microsoft opened pop-up stores in a number of malls across the country during the 2012 holiday season to sell its Surface tablet.

GE has attained its large market cap partly due to the diversity of the company, which has divisions that make everything from home appliances to products for the defense industry.

MARKET CAPITALIZATION: $231.22 billion

General Electric fact: General Electric has recently introduced a refrigerator that can dispense hot water.

Once known mostly for its personal computers, IBM has maintained its success by selling enterprise products.

MARKET CAPITALIZATION: $230.98 billion

IBM Fact: IBM recently sold its retail point-of-sale business to Toshiba.

Another giant oil company, Shell has managed to keep making money even as gas prices have risen and some consumers have moved towards fuel-efficient cars.

MARKET CAPITALIZATION: $229.36 billion

Royal Dutch Shell fact: Shell’s Technical Partnership with Scuderia Ferrari has resulted in 12 Drivers’ titles and 10 Constructors’ titles on the Formula One circuit.