Open Interest (abbrev. OI) reflects the number of open contracts on the market. Open Interest of 100,000 simply means this number of contracts to be either terminated or fulfilled.

Volume means the number of Contracts that were agreed among traders. In other words, if today's Volume is 10,000, it means that 10 thousand contracts were traded today. While the market Price represents the Demand and Supply Equilibrium, the Volume presents the number of contracts agreed.

Williams Accumulation/Distribution was created by Larry Williams. This indicator measures the pressure to Sell/Buy. That is also the reason why it's called Accumulation (Bulls control the market) and Distribution (the market is controlled by Bears).

Vertical Horizontal Filter (VHF) was created by Adam White. He described it in "Futures" magazine, August 1991. Its aim is to determine whether the asset prices are trending or not. If the VHF values begin to rise, it means a new trend just forms. If the VHF values fall, the trend is about to cease.

Volume Adjusted Moving Average – VAMA. It is a special type of Moving Average that takes into account not just the time period, but also the Volume of single days. Days with higher Volume are more important than the others.

Money Flow Index is a momentum oscillator. It was created by Laszlo Birinyi Jr. and measures the strength of investments comming into and out of the asset (in other words it measures the Volume during market rises and falls). So MFI indicator is mostly used to measure the strength of the trend prevailing on the market.