Silicon Valley has been the cradle of tech growth in the U.S. since the 1950s. As early players like Hewlett-Packard (HPQ 0.01%) matured, new start-ups arrived and became established tech titans on their own. Today, Silicon Valley is filled with so many tech companies that it's tough for new investors to know where to start investing their money.

In my opinion, there's one Silicon Valley company that's both a solid investment and an embodiment of the region's most innovative qualities -- Google (GOOG -1.10%) (GOOGL -1.09%), the search engine that evolved into an 800-pound gorilla on the Internet. Let's take a look at Google's core strengths, innovations, and blind spots.

Source: Image via Pixabay.

Google's strengths
Google's core strengths are easy to see. It processes 62% of the world's search queries on the Internet, according to Net Market Share. Its mobile OS, Android, is found on 77% of smartphones worldwide, according to IDC. Chrome is the second most popular web browser after Microsoft's (MSFT 0.10%) Internet Explorer.

Thanks to those strengths, Google generates the highest advertising revenue of any Internet advertising company. In 2014, Google reported $59.6 billion in advertising revenues. By comparison, Facebook (META -1.04%) posted $11.5 billion in advertising revenues last year. Google is also highly profitable. In 2014, its net income from continuing operations rose 4.4% annually to $13.9 billion, accounting for 21% of its revenues.

Since Google depends on advertising revenues instead of software sales, it can offer software products like Android, Chrome OS, and Drive for free. This tethers more users to its sprawling ecosystem while wreaking havoc on companies like Microsoft. To shore up its defenses against Google, Microsoft had to either reduce prices for Windows and Office licenses or give them away for free. Both strategies have taken a toll on its bottom line.

Google's innovations
Google depends heavily on search and ad revenues today, but that could change in the future if its "moon shots" evolve into revenue-generating businesses. Four key areas to watch are driverless cars, robotics, health care, and Internet connections for developing nations.

Google expects driverless cars to hit public roads by 2020. Google demonstrated prototype driverless cars last year, and is currently mapping out roads for these next-gen vehicles.

It also acquired Boston Dynamics, a leading manufacturer of military robots. These machines could fulfill various useful roles at home and abroad, although they also conjure up dystopian visions of a Google-dominated future. And that's only one of several robotics companies Google has purchased in the past couple of years.

In health care, Google has formed its own biotech subsidiary, Calico, which partnered with AbbVie last year to research and develop treatments for age-related diseases like cancer and Alzheimer's disease. It also initiated an ambitious human genome project to create an online database of biomarkers to help companies develop medications for various diseases, and has also developed medical devices, like a prototype contact lens that can read blood sugar levels from tears, which it licensed to Novartis last July.

Google's contact lens. Source: Google.

Google is also launching Wi-Fi weather balloons to deliver Internet access to developing nations and remote regions. These balloons can tether first-time Internet users to Google's ecosystem.

Google's blind spots
However, Google has three major weaknesses that can't be ignored.

First, Facebook is redefining the Internet by weaving its social network through third-party apps and sites. By tethering them to its News Feed, it offers advertisers a centralized location to deliver ads. As a result, Facebook is crushing Google -- which repeatedly failed at social networking -- in mobile display ad revenues. Research firm eMarketer claims that Facebook last year generated $3.54 billion in mobile display ad revenue in the U.S., compared to just $1.13 billion for Google.

Second, Google remains far behind Amazon (AMZN -1.66%) in product searches. Last year, Google chairman Eric Schmidt admitted that "more than twice" the number of people looking to buy something online started on Amazon as on Google. Amazon is now leveraging that strength to expand its Prime ecosystem through digital sales, hardware products like Fire TV, and local delivery options.

Lastly, Google is being beaten down by regulators. It currently faces an antitrust probe in the EU over allegations of using its "search bias" to promote its first-party sites over third-party ones, along with a separate investigation into its app bundling practices in Android. Since Google generates over a third of its revenue from Europe, adverse rulings there could impact its top-line growth.

Should you invest in Google?
Google's upside might remain limited until it can successfully cover those blind spots. But in my opinion, it's still a solid stock to own for the long run, and it could evolve into a much different company over the next few decades.