The technical indicators of the Forex market don’t take information from the air; they are all based on some of the market’s parameters and the appropriate calculation methods. Each indicator is calculated according to its own rules and there is no need to describe them all. In this article I’ll try to describe only the actual Forex market parameters that can fully describe the technical side of the Forex trading.
- Trend — a direction      of the price movement. Forex      market can be in some kind of trend      or go sideways. The trend itself can be measured      by its direction, starting/ending point, ranges and the inner      volatility.
 - Volatility —      a statistical measure of the number of the price changes      over a certain period of time.
 - Momentum — a measure      of price movement strength in a term of pips per tick.
 - Cyclicality —      it’s hard to be measured, but it still exists      on the financial markets (and on Forex too) and describes the      cyclical nature of some price movement.
 - Volume — the number      of the transactions (price changes for Forex) in a given      amount of time.
 - Support and resistance      levels — they can be hard to spot, but Forex market generally bounces off      of them or breaks them with a significant price action.
 - Traders’ expectations —      they can’t be seen from charts, but they are the part      of the technical picture of the market. Stop and limit orders      are the important parameters of the market that should be taken      seriously.
 
Some technical indicators use only one or two of these parameters; very few of the standard MetaTrader 4 indicators use more than two technical parameters. And I don’t know any indicators that are based on cyclicality or trader’s positions.

