G'day LR2,Saw the trades at the open on the Lse can you explain...

G'day LR2,
Saw the trades at the open on the Lse can you explain why some sales are decribed as Buy and some as Sell? I'm puzzled because arn't all sales both a buy and sell? you have mentioned this point before but I couldnt understand this fact. example is the nearly 4 million Rhep shares sold at 6.62p described as a SELL but surely somebody purchased these?
anyway good volume this ones finally moving up to were it belongs north of 25 cents + in line with its net asset backing. All the other drillers have moved up quite a bit and takeover fever is helping put back the value.