What is the logic behind intraday data recordings?
I have the 20s Wall Street intraday data, this way:

Company Name
5000 | 56 1/4
 200 | 55
1000 | 56 1/2

I would like to know what are these numbers about.
I know the first column to be the numbers of shares, and the second
one the price (for each) in dollars.
The problem is that there's no specifics about those numbers: are they
sold stocks or buyed ones? I can't understand it. How do they work?
I would like to create a graph with them (the one you usually watch on
the News) , to represent the oscillation
of the Companyes, and I need to know how can I represent it with those
numbers.

So, I would like to know what do those numbers are... :-)

Thank You

It seems you biggest question is whether the transaction referred to
is a buy or a sell. It is impossible to say with the data you have
provided, but in some ways it is both. What you see posted with the
data is the volume of the trade and the trade price. To determine if
the trade is a buy or a sell, you will need to know if the bid was hit
or the ask. In any trade there is always a bid price and an ask price.
For example; 55 bid, 56 asked. 55 is what someone is willing to buy
for and 56 is what someone is willing to sell for. If a trade goes off
for 100 at 55, then you know that someone accepted the bid of 55 --
they sold to the bidder, but someone bought too in that THEY offered
the bid. That is why I say "both". But for your purposes, that would
be a sell. If it was posted as 200 at 56, you could assume someone put
an order in to buy 200 shares at the market, or at the ask price.

So to have your answer you will need to know the bid and the ask at
the time of the trade -- data that is not usually available. As a
proxy, some assume a stock that drops a "tick" on the trade is a sell
and a stock that goes up a "tick" is a buy -- that is how many of the
accumulation indicators work. So those graphs you are referring to may
be using that protocol.

Make sense?