Demand for exchange traded funds remains strong. Year-to-date, investors have directed some $201 billion into ETFs, on track to reach the $243 billion invested during 2014 -- according to ETF.com. ETFs are a popular alternative to stocks, experts say. ‘ETFs provide investors access to the market in a very low-cost, diversified and transparent way,’ said Jane Leung, head of iShares precision exposures at BlackRock. She said ETFs are the blend of both worlds of stocks and mutual funds. ETFs trade on an exchange like stocks and can be professionally managed like mutual funds. Investors may buy and sell ETFs on their own timetable in what’s called a market order. But they can also buy and sell ETFs at a fixed price, known as a limit order. ‘Limit orders allow you to set a limit [a specific price], at where you wish to get the trade done,’ she said. ‘And you basically will get the trade processed at that price or better depending on where the market is, so you do have to think about whether or not you’re in a fast moving or stable market.’ With limit orders, if the share price never reaches the target price, the transaction will not be processed. Another way to buy ETFs is via a stop order. Scott Gamm speaks with Leung in New York.