Read the two sides before the old print
In this separate, illustrative Bharat Foods snapshot, the last traded price (LTP) is ₹500. The best bid is ₹499 for 200 shares: the highest price in the displayed waiting buy orders. The best ask is ₹501 for 100 shares: the lowest price in the displayed waiting sell orders. These are prices offered by different participants, not estimates of the company's value.
If an eligible seller arrives for up to 200 shares while that bid still waits, ₹499 is the first available buying price. If an eligible buyer arrives for up to 100 while that ask still waits, ₹501 is the first available selling price. The quote can disappear, trade partly or change before a new order reaches it; it is an available term at the snapshot, not an execution promise.
LTP remains ₹500 until another trade is recorded. A bid moving from ₹499 to ₹498 would change the current quote without rewriting the last completed trade. That is the difference Chapter 02.01 prepared you to see.
Three numbers, three different claims
Tap each field in the same invented ₹500 screen. The quantities belong to waiting orders, not to your existing ten-share holding.
The book gives prices and quantities on each side. It does not show why those participants placed their orders.
The spread is the gap
Spread = best ask − best bid. Here it is ₹501 − ₹499 = ₹2 a share, or 0.4% of the ₹500 reference price. The percentage is only a convenient comparison; the rupee gap is the observable quote.
Suppose, as an illustration, you bought ten additional shares at the ask and immediately sold them at the bid, with both quotes unchanged. You would pay ₹5,010 and receive ₹4,990: a ₹20 gross loss before brokerage, taxes and other costs. No additional shares are actually bought or sold in the continuing story.
The spread is not a separate fee a broker takes. It is the difference between the currently available prices for immediate buying and selling. It can narrow, widen or vanish from this exact screen as orders arrive, trade or cancel. A tight spread alone does not guarantee enough quantity for your full order.
More on the spread as a trading cost (optional)
The earlier cost lesson uses the spread in a complete round trip with charges and price impact. Here the narrower job is to identify the two live sides of a quote before estimating any order's price.
Deeper study
LTP is ₹500, the best bid is ₹499 and the best ask is ₹501. No trade occurs, but the ₹499 bid is cancelled. What happens to LTP?
What the spread cannot answer
The ₹2 gap does not tell you which side will move next, whether one trader quoted both sides, or how much of a larger order can complete near these prices. A 150-share buyer facing only 100 displayed at ₹501 may have to reach a higher ask; the next lesson will show where to look.
Use bid and ask when the question is what is available now for a stated quantity? Do not use an old LTP as that answer. The next page opens the five displayed price levels behind each best quote.