XYZ Bid 100.20 x 500 Ask 100.24 x 300 Last 100.22 Vol 1,240,000
Read it as: "Best buyers will pay 100.20 for up to 500 shares; best sellers want 100.24 for 300 shares; the last trade printed at 100.22; 1.24 M shares have changed hands today."
Can Level-1 warn you about "walking the book" on a large order?
No — Level-1 shows only the top of book; deeper prices require Level-2.
Recall Feynman: explain to a 12-year-old
Imagine a toy market. On one side, kids shout the most they'll pay for a sticker — the loudest offer is the Bid. On the other side, kids shout the least they'll sell it for — the cheapest is the Ask. The gap between "I'll pay 20" and "I'll sell for 22" is the spread. If you want a sticker right now, you pay the seller's 22; if you want to sell right now, you take the buyer's 20. The Last number is just the price the previous kid actually traded at — old news. That's a whole Level-1 quote!
Level-1 quote ek stock ka sabse basic "live price snapshot" hota hai. Ismein char main cheezein dekhni hain: Bid (sabse zyada jo koi buyer dene ko tayaar hai), Ask/Offer (sabse kam jis pe koi seller bechne ko tayaar hai), inke saath sizes (kitne shares available hain), aur Last (pichhla actual trade jis price pe hua). Yaad rakho — agar tum abhi market order se kharidoge to Ask price pay karoge, aur abhi bechoge to Bid price milega. Last sirf history hai, wo tumhara fill price zaroori nahi.
Sabse zaroori concept hai spread = Ask − Bid. Ye tumhara hidden cost hai. Agar tum turant kharid ke turant bech do, to tum ye spread lose kar dete ho — isliye ise "cost of liquidity" kehte hain. Tight spread matlab stock liquid hai, sabko easily trade karne milta hai; wide spread matlab thin/illiquid stock, jahan trading mehenga padta hai. Mid = (Bid+Ask)/2 ek fair reference value hai, lekin normal market order us pe execute nahi hota.
Ek common galti: log Bid size bada dekh ke soch lete hain "price ab upar jayega". Ye sirf ek weak hint hai — orders millisecond mein cancel ho sakte hain, spoofing bhi hoti hai. Isliye size ko context ki tarah lo, signal ki tarah nahi. Doosri galti: bade order ke liye Level-1 kaafi nahi hai, kyunki agar tumhara order Ask size se bada hua to tum "book walk" karoge aur higher price pe fill hoge — uske liye Level-2 chahiye. Simple mantra rakho: "Buy the Ask, Sell the Bid, Last is dead."
