What is a mutual fund?
Let's say that you want to invest in the stock market.  Choosing and investing in only one stock is risky.  You can lower your risk by diversifying, or investing in lots of different stocks.  However, you have some problems with this:  When you buy stocks directly, you have to buy whole shares, and you don't have enough money to buy even one whole share of all the stocks you want to invest in. You aren't even sure which stocks you should buy. A mutual fund solves both of these problems.  You get together with other investors and pool your money together to buy a group of stocks.  That way, your investment is diversified in lots of different stocks without having to have enough money to buy whole shares of each one.  And the mutual fund has a manager that chooses which stocks the fund will invest in, so you don't have to pick. There are lots of mutual funds to choose from, with as many different objectives as you can imagine.  Some invest in large companies, others small; some invest in a certain sector of companies (utilities or health care, for example), some invest in stocks that pay a dividend, others are focused on growth.  Some funds don't invest in stocks at all; they might invest in bonds, real estate, or precious metals.  Some funds are actively managed, where the manager actively buys and sells different stocks in the fund continuously (and takes a fee for his services), and others simply invest in a list of stocks and rarely buy or sell (these are called index funds). To answer your question, yes, the JPMorgan Emerging Markets Equity Fund is a mutual fund.  It is an actively-managed stock mutual fund that attempts to invest in growing companies that do business in countries with rapidly developing economies. The simple answer is: YES, the JP Morgan emerging markets equity fund is a mutual fund. A mutual fund is a pooling of money from investors to invest in stocks and bonds. Investors in mutual funds arrive there in different ways. Some get there via their company 401K, others by an IRA, still others as a taxable account. The fund can be sold by the company directly or through a broker. You can also have a fund of funds. So the investors are other funds.  Some investors are only indirect investors. They are owed a pension by a past or current employer, and the pension fund has invested in a mutual fund.
"First, what structure does your index fund have?  If it is an open-end mutual fund, there are no bid/ask spread as the structure of this security is that it is priced once a day and transactions are done with that price.  If it is an exchange-traded fund, then the question becomes how well are authorized participants taking advantage of the spread to make the fund track the index well?  This is where you have to get into the Creation and Redemption unit construct of the exchange-traded fund where there are ""in-kind"" transactions done to either create new shares of the fund or redeem out shares of the fund.  In either case, you are making some serious assumptions about the structure of the fund that don't make sense given how these are built. Index funds have lower expense ratios and are thus cheaper than other mutual funds that may take on more costs.  If you want suggested reading on this, look at the investing books of John C. Bogle who studied some of this rather extensively, in addition to being one of the first to create an index fund that became known as ""Bogle's Folly,"" where a couple of key ones would be ""Common Sense on Mutual Funds: New Imperatives for the Intelligent Investor"" and ""Bogle on Mutual Funds: New Perspectives for the Intelligent Investor."" In the case of an open-end fund, there has to be a portion of the fund in cash to handle transaction costs of running the fund as there are management fees to come from running the fund in addition to dividends from the stocks that have to be carefully re-invested and other matters that make this quite easy to note.  Vanguard 500 Index Investor portfolio(VFINX) has .38% in cash as an example here where you could look at any open-end mutual fund's portfolio and notice that there may well be some in cash as part of how the fund is managed.  It’s the Execution, Stupid would be one of a few articles that looks at the idea of ""tracking error"" or how well does an index fund actually track the index where it can be noted that in some cases, there can be a little bit of active management in the fund. Just as a minor side note, when I lived in the US I did invest in index funds and found them to be a good investment.  I'd still recommend them though I'd argue that while some want to see these as really simple investments, there can be details that make them quite interesting to my mind. How is its price set then? The price is computed by taking the sum value of all the assets of the fund minus the liabilities and divided by the number of outstanding shares.  The price of the assets would include the closing price on the stock rather than a bid or ask, similar pricing for bonds held by the fund, derivatives and cash equivalents.  Similarly, the liabilities would be costs a fund has to pay that may not have been paid yet such as management fees, brokerage costs, etc. Is it a weighted average of all the underlying stock spreads, or does   it stand on its own and stems from the usual supply & demand laws ? There isn't any spread used in determining the ""Net Asset Value"" for the fund.  The fund prices are determined after the market is closed and so a closing price can be used for stocks. The liabilities could include the costs to run the fund as part of the accounting in the fund, that most items have to come down to either being an asset, something with a positive value, or a liability, something with a negative value. Something to consider also is the size of the fund.  With over $7,000,000,000 in assets, a .01% amount is still $700,000 which is quite a large amount in some ways." "1) When it says ""an investment or mutual fund"", is a mutual fund not   an investment? If no, what is the definition of an investment? A mutual fund is indeed an investment. The article probably mentions  mutual funds separately from other investments because it is not uncommon for mutual funds to give you the option to automatically reinvest dividends and capital gains.    2) When it says ""In terms of stocks"", why does it only mention   distribution of dividends but not distribution of capital gains? Since distributions are received as cash deposits they can be used to buy more of the stock. Capital gains, on the other hand, occur when an asset increases in value. These gains are realized when the asset is sold. In the case of stocks, reinvestment of capital gains doesn't make much sense since buying more stock after selling it to realize capital gains results in you owning as much stock as you had before you realized the gains. 3) When it says ""In terms of mutual funds"", it says about ""the   reinvestment of distributions and dividends"". Does ""distributions"" not   include distributions of ""dividends""? why does it mention   ""distributions"" parallel to ""dividends""? Used in this setting, dividend and distribution are synonymous, which is highlighted by the way they are used in parallel. 4) Does reinvestment only apply to interest or dividends, but not to   capital gain? Reinvestment only applies to dividends in the case of stocks. Mutual funds must distribute capital gains to shareholders, making these distributions essentially cash dividends, usually as a special end of year distribution. If you've requested automatic reinvestment, the fund will buy more shares with these capital gain distributions as well." What explains the most of the future returns of a portfolio is the allocation between asset classes. In the long term, stock investments are almost certain to return more than any other kinds of investments. For 40+ years, I would choose a portfolio of 100% stocks. How to construct the portfolio, then? Diversification is the key. You should diversify in time (don't put a large sum of money into your stock portfolio immediately; if you have a large sum to invest, spread it around several years). You should diversify based on company size (invest in both large and small companies). You should also diversify internationally (don't invest in just US companies). If you prefer to pick individual stocks, 20 very carefully selected stocks may provide enough diversification if you keep diversification in mind during stock picking. However, careful stock picking cannot be expected to yield excess returns, and if you pick stocks manually, you need to rebalance your portfolio occasionally. Thus, if you're lazy, I would recommend a mutual fund, or many mutual funds if you have difficulty finding a low-cost one that is internationally diversified. The most important consideration is the cost. You cannot expect careful fund selection to yield excess returns before expenses. However, the expenses are certain costs, so prefer low-cost funds. Almost always this means picking index funds. Avoid funds that have a small number of stocks, because they typically invest only in the largest companies, which means you fail to get diversification in company size. So, instead of Euro STOXX 50, select STOXX 600 when investing to the European market. ETFs may have lower costs than traditional mutual funds, so keep ETFs in mind when selecting the mutual funds in which to invest. For international diversification, do not forget emerging markets. It is not excessive to invest e.g. 20% to emerging markets. Emerging markets have a higher risk but they also have a higher return. A portfolio that does not include emerging markets is not in my opinion well diversified. When getting close to retirement age, I would consider increasing the percentage of bonds in the portfolio. This should be done primarily by putting additional money to bonds instead of selling existing investments to avoid additional taxes (not sure if this applies to other taxation systems than the Finnish one). Bond investments are best made though low-cost mutual funds as well. Keep bond investments in your local currency and risk-free assets (i.e. select US government bonds). Whatever you do, remember that historical return is no guarantee of future return. Actually, the opposite may be true: there is a mean reversion law. If a particular investment has returned well in the past, it often means its price has gone up, making it more likely that the price goes down in the future. So don't select a fund based on its historical return; instead, select a fund based on low costs. However, I'm 99% certain that over a period of 40 years, stocks will return better than other investments. In addition to fund costs, taxes are the other certain thing that will be deducted from your returns. Research what options you have to reduce the taxes you need to pay. 401-K was explained in another answer; this may be a good option. Some things recommended in other answers that I would avoid: This is really an extended comment on the last paragraph of @BenMiller's answer. When (the manager of) a mutual fund sells securities that the fund holds for a profit, or receives dividends (stock dividends, bond interest, etc.), the fund has the option of paying taxes on that money (at corporate rates) and distributing the rest to shareholders in the fund, or passing on the entire amount (categorized as dividends, qualified dividends, net short-term capital gains, and net long-term capital gains) to the shareholders who then pay taxes on the money that they receive at their own respective tax rates. (If the net gains are negative, i.e. losses, they are not passed on to the shareholders. See the last paragraph below).  A shareholder doesn't have to reinvest the distribution amount into the mutual fund: the option of receiving the money as cash always exists, as does the option of investing the distribution into a different mutual fund in the same family, e.g. invest the distributions from Vanguard's S&P 500 Index Fund into Vanguard's Total Bond Index Fund (and/or vice versa). This last can be done without needing a brokerage account, but doing it across fund families will require the money to transit through a brokerage account or a personal account. Such cross-transfers can be helpful in reducing the amounts of money being transferred in re-balancing asset allocations as is recommended be done once or twice a year. Those investing in load funds instead of no-load funds should keep in mind that several load funds waive the load for re-investment of distributions but some funds don't: the sales charge for the reinvestment is pure profit for the fund if the fund was purchased directly or passed on to the brokerage if the fund was purchased through a brokerage account. As Ben points out, a shareholder in a mutual fund must pay taxes (in the appropriate categories) on the distributions  from the fund even though no actual cash has been received because the entire distribution has been reinvested. It is worth keeping in mind that when the mutual fund declares a distribution (say $1.22 a share), the Net Asset Value per share drops by the same amount (assuming no change in the prices of the securities that the fund holds) and the new shares issued are at this lower price. That is, there is no change in the value of the investment: if you had $10,000 in the fund the day before the distribution was declared, you still have $10,000 after the distribution is declared but you own more shares in the fund than you had previously. (In actuality, the new shares appear in your account a couple of days later, not immediately when the distribution is declared).  In short, a distribution  from a mutual fund that is re-invested leads to no change in your net assets, but does increase your tax liability. Ditto for a distribution that is taken as cash or re-invested elsewhere. As a final remark, net capital losses inside a mutual fund are not distributed to shareholders but are retained within the fund to be written off against future capital gains. See also this previous answer  or this one. "As you alluded to in your question, there is not one answer that will be true for all mutual funds.  In fact, I would argue the question is not specific to mutual funds but can be applied to almost anyone who must make an investment decision: a mutual fund manager, hedge fund manager, or an individual investor. Even though money going into a company 401(k) retirement savings plan is typically automatically allocated to different funds as we have specified, this is generally not the case for other investment accounts. For example, I also have a Roth IRA in which I have some money from each paycheck direct deposited and it's up to me to decide whether to leave that money in cash or to invest it somewhere else.  Every time you invest more money into a mutual fund, the fund manager has the same decision to make. There are two commonly used mutual fund figures that relate to your question: turnover rate, and cash reserves. Turnover rate measures the percent of a fund's portfolio that changes every year.  For example, a turnover rate of 100% indicates that a fund replaces every asset it held at the beginning of the year with something else at the end of the year – funds with turnover rates greater than 100% average a holding period for a given asset of less than one year, and funds with turnover rates less than 100% average a holding period for a given asset of more than one year. Cash reserves simply measure the amount of money funds choose to keep as cash instead of investing in other assets. Another important distinction to make is between actively managed funds and passively managed funds. Passively managed funds are often referred to as ""index funds"" and have as their goal only to match the returns of a given index or some other benchmark.  Actively managed funds on the other hand try to beat the market by exploiting so-called market inefficiencies; e.g. buying undervalued assets, selling overvalued assets, ""timing"" the market, etc. To answer your question for a specific fund, I would encourage you to look at the fund's prospectus. I take as one example of a passively managed fund the Vanguard 500 Index Fund (VFINX), a mutual fund that was created to track the S&P 500.  In its prospectus, the fund states that, ""to track its target index as closely as possible, the Fund attempts to remain fully invested in stocks"". Furthermore, the prospectus states that ""the fund's daily cash balance may be invested in one or more Vanguard CMT Funds, which are very low-cost money market funds.""  Therefore, we would expect both this fund's turnover rate and cash reserves to be extremely low. When we look at its portfolio composition, we see this is true – it is currently at a 4.8% turnover rate and holds 0.0% in short term reserves.  Therefore, we can assume this fund is regularly purchasing shares (similar to a dollar cost averaging strategy) instead of holding on to cash and purchasing shares together at a specific time. For actively managed funds, the picture will tend to look a little different.  For example, if we look at the Magellan Fund's portfolio composition, we can see it has a turnover rate of 42%, and holds around .95% in cash/short term reserves.  In this case, we can safely guess that trading activity may not be as regular as a passively managed fund, as an active manager attempts to time the market.  You may find mutual funds that have much higher cash reserves – perhaps 10% or even more. Granted, it is impossible to know the exact trading strategy of a mutual fund, and for good reason – if we knew for example, that a fund purchases shares every day at 2:30PM in order to realign with the S&P 500, then sellers of S&P components could up the prices at that time to exploit the mutual fund's trade strategy.  Large traders are constantly trying to find ways to conceal their actual trading activity in order to avoid these exact problems. Finally, I feel obligated to note that it is important to keep in mind that trade frequency is linked to transactions costs – in general, the more frequently an investment manager (whether it be you or a mutual fund manager) executes trades, the more that manager will lose in transactions costs." "Most mutual funds are designed to make the investment banks that sell them money, not to make investers money. They do this by taking significant fees out. Because they make lots of money on these funds, they advertise them a lot, and give them important-sounding names, like ""Advanced technology global diversity long term appreciation"".  Index funds are the exception; they attempt to mirror the performance of a specific index (such as the S&P 500 index). They generally have very low fees." "If your intention is to purchase ETFs on a regular basis (like $x per month), then ETFs may not make sense.  You may have to pay a fixed transaction cost like you were buying a stock for each purchase.  In a similar no load mutual fund, there are more likely to be no transaction costs (depending on how it is bought).   The above paragraph is not very definitive, and is really dependent upon how you would purchase either ETFs or Mutual funds.  For example if you have a Fidelity brokerage account, they may let you buy certain ETFs commission free.  Okay then either ETFs make great sense.  It would not make sense to buy ones that they charge $35 per transaction if you have regular transactions that are smallish. The last two questions seem to be asking if you should buy MF or buy stocks directly.  For most people the later is a losing proposition.  They do not have the time or ability to buy stocks directly, effectively.  Even if they did they may not have the capital to make enough of a difference when one considers all the cost involved.  However, if that kind of thing interests you, perhaps you should dabble.  Start out small and look at the higher costs of doing so as part of the ""cost of doing business""." Bond ETFs are just another way to buy a bond mutual fund.  An ETF lets you trade mutual fund shares the way you trade stocks, in small share-size increments.  The content of this answer applies equally to both stock and bond funds. If you are intending to buy and hold these securities, your main concerns should be purchase fees and expense ratios.  Different brokerages will charge you different amounts to purchase these securities.  Some brokerages have their own mutual funds for which they charge no trading fees, but they charge trading fees for ETFs.  Brokerage A will let you buy Brokerage A's mutual funds for no trading fee but will charge a fee if you purchase Brokerage B's mutual fund in your Brokerage A account. Some brokerages have multiple classes of the same mutual fund.  For example, Vanguard for many of its mutual funds has an Investor class (minimum $3,000 initial investment), Admiral class (minimum $10,000 initial investment), and an ETF (share price as initial investment).  Investor class has the highest expense ratio (ER).  Admiral class and the ETF generally have much lower ER, usually the same number.  For example, Vanguard's Total Bond Market Index mutual fund has Investor class (symbol VBMFX) with 0.16% ER, Admiral (symbol VBTLX) with 0.06% ER, and ETF (symbol BND) with 0.06% ER (same as Admiral).  See Vanguard ETF/mutual fund comparison page.  Note that you can initially buy Investor class shares with Vanguard and Vanguard will automatically convert them to the lower-ER Admiral class shares when your investment has grown to the Admiral threshold. Choosing your broker and your funds may end up being more important than choosing the form of mutual fund versus ETF.  Some brokers charge very high purchase/redemption fees for mutual funds.  Many brokers have no ETFs that they will trade for free.  Between funds, index funds are passively managed and are just designed to track a certain index; they have lower ERs.  Actively managed funds are run by managers who try to beat the market; they have higher ERs and tend to actually fall below the performance of index funds, a double whammy. See also Vanguard's explanation of mutual funds vs. ETFs at Vanguard. See also Investopedia's explanation of mutual funds vs. ETFs in general.