hi can somebody explain to me the concept of bids/offers?

from what i understand, BID is the max price that a person is willing to pay for a particular stock while OFFER is the min price a person is willing to get for a the stock. so in my OSK online trading window. i see something like this

BIDS/OFFERS 3buy 2buy 1buy last 1sell 2sell 3sell
Price 2.5 2.6 2.7 2.8 2.8 2.9 3
Quantity 1000 1500 5000 50 2000 3000 1000



what does it mean by '1buy' or '2buy'? does '1buy' means its currently the highest buy price that a person is willing to pay and '2buy' the 2nd highest?


then what happen when the highest BID is 2.7 but the lowest OFFER is 2.8? does it mean that no stock trade could be made bcoz no price can be agreed on?