Part 1: Front-end, back-end, APIs and requirements

Module 9 · Sun 13 Sep, morning

PM ki tech fluency engineers ke saath achhe se kaam karne ke baare mein hai - feasibility aur clarity - coding nahi. Flow: user front-end par action leta hai (jo use dikhta hai) → API request le jaata hai (messenger) → back-end aur database rules lagaate hain aur state store karte hain. Endpoint woh URL hai jise front-end call karta hai.

• HTTP methods: GET = fetch, POST = create, PATCH = update, DELETE = remove. Class cart example: menu dekhna GET hai; cart mein add karna POST hai, aur back-end important fields check karta hai.
• Status codes: 200 OK, 201 created, 204 success bina content, 400 bad input, 401 logged in nahi, 403 allowed nahi, 500 server error. Code back-end ka hai; user ko aage kya dikhe, yeh PM ka call hai.
• Clear API contracts front-end/back-end rework rokte hain.

Functional requirements = system kya karta hai (acceptance criteria se testable). Non-functional requirements = kitni achhi tarah: latency (round-trip time), availability, rate limiting (ek time window mein requests par cap, expected usage aur risk ke hisaab se), scalability.

PMs product behaviour aur strategy ke owner hain; BAs zyadatar requirement gathering aur docs ke. PMs behaviour events aur analytics se dekhte hain, raw API logs se nahi. Usage ka forecast feature by feature karo. Rule of thumb: measurable targets rakho aur success aur failure, dono states design karo.