We shall try to understand the term called "spread" and how it results in big moves.
Lets not try to deal in high language.We shall keep it simple.According to me a spread is a length of a particular order/collective orders.
Lets take an example. Say Market is making down move and say Nifty is at 5475 .Now say we want to buy 100 lots of Nifty between 5500 -5550. Now what I do is like this.
I place my order like this:
Quantity - 100 lots
Trigger price :5500
Limit price : 5550
A trigger price refers to a price if triggered or reached results in execution of our orders.So that means If Nifty reaches 5500 level our orders start executing.
What about limit price.It is a price beyond which we don't want to buy. Its a Max limit,seal,cap.Why limit? because we don't want to be buying too high as we want market to move up. Rule: buy low sell high. So in this case we don't want to buy over and above 5550.
So the difference between A Limit price i.e:5550 and the trigger price i.e:5500 i.e:50 points is called as spread in this case.
Another question :Why 50 points spread?Answer is :I want to buy 100 lots and I may not have 100 lots of sell orders ( To match my buy orders ) at 5500.Hence I am putting a spread or net.Its like a fisher man spreading across his net across a diameter of the sea.He knows if he puts his net at a single place he won't get enough fishes or he may not get the fish at all.
Now what? The 100 orders may get executed like this.
20 Orders executed @ 5500
12 Orders executed @ 5510
15 Orders executed @ 5515
10 Orders executed @ 5528
5 Orders executed @ 5535
6 Orders executed @ 5540
12 Orders executed @ 5547
20 Orders executed @ 5550
Total = 100 Lots of Nifty bought starting from 5500 to 5550.Thats how spread works. Reverse it for selling orders.
Once you have grasped the above concept ,now see how a big pocket can bulldoze the market.
A Big pocket trader always looks for a good location to enter the market. It can be a Big round Number or a particular FIB retracement (31.8% or 61%) or a touch and bounce of trendline.
In this example assume that its 5500.His Trigger price is 5500 and limit price is 5600 means he is laying a net between 5500 - 5600 for 5000 lots of Nifty.
Now lets say he places his buying orders at 10 AM. now its like this.
1000 orders executed @5500
800 orders executed @5510
200 orders executed @5520
400 orders executed @5525
200 orders executed @5540
600 orders executed @5550
400 orders executed @5560
500 orders executed @5570
200 orders executed @5575
200 orders executed @5580
500 orders executed @5600
Say by 10.30 all these orders got executed. Now the result will be a bullish candle on the 30 Min chart as shown below.
The essential point here is to show how a candle opens and how it closes. Different people interpret spread in different terms.Here we are trying to understand how a buyers or sellers spread of orders can affect a movement of market and formation of candles. Here the transaction time was in between 10 am to 10.30 AM and the candle opened at 5500 and closed at 5600.So a bullish 30 Minute candle made a movement of 100 points in half an hour. Bid/ask etc we shall try to understand later.