With exchange-traded funds making it so easy for investors to put their money to work, it's no wonder so many people have embraced ETFs as their favorite investment. But the proliferation of ETFs presents investors with a conundrum: how to choose from among an estimated 1,350 different funds, with more coming out all the time.

To help make it a little easier to find those precious needles in the haystack of ETFs, I decided to look at some of the biggest families of exchange-traded funds in today's market. Today, let's turn to the industry leader in ETFs: BlackRock's iShares.

No, Steve Jobs didn't come up with these ETFs
Although their name might suggest a relationship with the latest smartphone or tablet products from Cupertino, iShares have their origins in a series of ETFs that Morgan Stanley and Barclays released in the early 1990s. Responding to the SPDR series that pioneered ETFs, these funds, originally dubbed World Equity Benchmark Series, or WEBS, eventually changed their name to iShares in 2000.

Since then, Barclays built the ETF series into the largest in the world. It sold the iShares division to BlackRock in 2009, but iShares remains the ETF provider with the most assets under management.

An all-purpose family
From its humble beginnings, iShares has grown to offer more than 200 ETFs in all sorts of areas. For the most part, if you can think of a type of asset, sector, geographical location, or investing strategy, iShares has a fund that can serve you. For instance, here's a small sample of its wares:

  • These days, everyone seems to want ETFs that can pay big dividends. With the iShares DJ Select Dividend ETF (NYSE: DVY), you get exposure to a host of dividend stocks with strong track records of healthy payouts. If traditional stocks don't give you enough of a return, then you may prefer the iShares S&P US Preferred Stock Index (NYSE: PFF), which uses preferred shares of well-known companies to boost the ETF's yield.
  • In a period during which international investing has taken off as a more profitable alternative to stateside stocks, iShares has become famous for its single-country funds. Tied to the MSCI indexes -- which originally stood for Morgan Stanley Capital International before the firm separated from Morgan Stanley in 2009 -- ETFs like iShares MSCI Austria Investable Market (NYSE: EWO) and iShares MSCI Singapore Index (NYSE: EWS) give iShares investors targeted exposure to dozens of countries around the world.
  • SPDRs are well-known for their sector-specific funds, but iShares gives investors an alternative. For instance, the iShares DJ US Energy ETF (NYSE: IYE) may not be as popular as its SPDR counterpart, but it tracks a similar, though slightly different, index of energy stocks.
  • As precious metals entered a huge bull run, iShares was there, offering its iShares Silver Trust (NYSE: SLV) to present a share-based alternative to buying bulky bullion bars of the white metal.
  • Most recently, emerging markets have become popular not only for their stocks but also for higher interest rates on fixed-income securities. iShares JPMorgan USD Emerging Markets Bond (NYSE: EMB) lets you invest in emerging-market-issued bonds without the full currency risk non-dollar-denominated securities have.

There's no doubt that iShares has arguably the most complete set of ETF offerings in the industry today. But that doesn't mean it doesn't have competition.

Strategic moves versus competitors
A couple of years ago, iShares identified a trend early on in the ETF industry toward commission-free funds. It partnered with online broker Fidelity to offer 30 of its ETFs to Fidelity customers with no commissions. That has helped raise its profile and stay competitive against up-and-coming ETF providers.

Still, it hasn't defeated its competition entirely. Vanguard in particular tends to have less costly funds, and in a few key areas such as emerging market stock ETFs, Vanguard has wrested leadership of some market niches away from iShares. With such a massive asset advantage over its peers, though, iShares would have to stumble badly to give up its overall lead.

The right ETF for you?
If you're an ETF investor, you'll inevitably run into iShares ETFs that will meet your needs. The question is whether those ETFs are the best available. With its size advantage, iShares often gives you advantages in favorable buy and sell trade executions that smaller providers lack. Although you'll want to look closely at expense ratios to make sure that cheaper alternatives aren't available, iShares definitely warrant attention as you shop around for suitable ETFs for your portfolio.

If you like ETFs, you won't want to miss The Motley Fool's free special report on exchange-traded funds. You'll find the names of three ETFs we think have the potential to hit home runs over the long haul.

Tune in every Monday and Wednesday for Dan's columns on retirement, investing, and personal finance. You can follow him on Twitter here.