Did you see a unicorn in 2015? Many investors did in the shape of an Uber, Airbnb or Snapchat. If you didn’t know what a unicorn was, you could look it up on Investopedia.

Investopedia wrote 672 terms in 2015 covering every topic relating to finance, business and economics. From political risk insurance to Anonymous (Internet Group), we informed investors to keep them ahead of the game.

The year started off with an attack on the French satirical newspaper Charlie Hedbo, and in April Iran agreed to a deal to limit their nuclear capabilities in return for a relaxation of economic sanctions. In the first six months of the year the unemployment rate in the U.S. fell from almost 6% to nearly 5% as the job market in the U.S. finally shook off the lingering effects of The Great Recession.

The world economy was big news as both Europe and China continued to show weakness, the price of oil continued to slide to levels not seen in six years and the U.S. dollar gained value month after month.

Were these the things on the minds of investors this year? Our list of the top 10 terms of 2015 has some items that you would expect and a few surprises:

10. Backdoor Roth IRA

Coming in at number 10, Backdoor Roth IRA may offer anecdotal evidence that older savers are looking to build a bigger nest egg. A “backdoor” Roth IRA allows wealthy individuals who have reached their contribution limit for a regular Roth IRA to contribute more to retirement. As more than 10,000 boomers retire every day and the threat of a retirement crisis looms, investors are looking for new ways to save for retirement.

9. Fintech

Fintech has been a buzzword for a few years now and has taken center stage as robo-advisors​ and mobile apps for trading stocks threaten to bring down “legacy” financial companies. The rise of fintech will continue as Millennials​, tethered to their mobile devices, look for new ways to “hack” the investing world.

8. Gamma Hedging

Gamma Hedging is an active trading strategy meant to hedge risk on options trades. Gamma hedging, tactical trading and intraday momentum used to be for hedge fund managers exclusively, but as technology disrupts many professions that had high bars of entry, more retail investors are becoming sophisticated active traders.

7. Tactical Trading

Tactical trading describes the strategy of active traders, particularly hedge fund traders. As technology disrupts investing – as it has done in so many seemingly permanent domains of life – many investors are becoming more actively involved with alternative investing strategies.

6. Intraday Momentum Index

The Intraday Momentum Index is a technical indicator used by day traders to signal when a stock is trending up or down. High volatility is good for day traders, and many traders were looking for ways to capitalize on markets’ high volatility this year, in particular over the summer when stock market gyrations gave many investors whiplash.

5. Unicorn

The high-profile success of tech startups like Snapchat and Uber, with their valuations at over one-billion dollars and negative cash flows, prompted skeptical investors to label them “unicorns”: mythical creatures that can’t be real.

4. Exchange-Traded Mutual Fund

As fees increase and returns languish for traditional mutual funds, investors are researching new products, like ETMFs, that combine the advantages of investment strategies of an actively managed mutual fund and the performance and tax efficiencies of an ETF.

3. Negative Interest Rate Policy

The European Central Bank experimented with unconventional monetary policy in 2015 to fight off deflation and pull Europe’s economy out of the doldrums. Negative interest rates penalize savers by making them pay to save. For example, in a regular savings account that offers 5% interest, when you deposit $100, the bank pays you $5 at the end of the year. With a negative interest rate of 5%, if you deposit $100, at the end of the year your bank account only has $95 in it.

2. Grexit​ / Brexit

In 2015, the global economy was shaken by the possibility of a Greek default on sovereign debt and the failure of the Eurozone​ as a common currency union. The discussion of Great Britain and Greece exiting the EU prompted us to create these terms.

1. Smart Beta

Smart Beta is a new, popular financial product that attempts to beat indexed funds, but many investors are still not familiar with it. The popularity of smart beta in the industry this year led it to being Investopedia's top term of the year. Because the terms is so new and asset management firms don’t always mean the same thing when they use it, investors looked for a second opinion on Investopedia.

Our top 10 terms for 2015 read like a diary of the most important events in finance and economics. Will Investopedia help you find out what 2016 holds?