Every investor worthy of the title knows that it is essential to keep funds liquid in a traditional savings account. However, keeping excess sums of money in savings accounts for the long term is not a wise investment strategy as commonly the interest rates earned do not keep pace with the average rate of inflation.
Money market funds are generally believed to be a safe (albeit uninsured) alternative to standard savings accounts, as they are considered to be a liquid investment interest with a slightly higher rate of return then a savings account.
Money market funds are a good place to invest money when the economy is taking a downward stumble as historically, there has been very little negative impact on money market funds.
Although money market funds do not have the protection of the Federal Government insurance backing them, they are typically considered to be safe investments and many times even portfolio managers use them to store the surplus cash of their clients before investing.