What are 'lab standards' and why are they important in chemistry?

Assalam-o-Alaikum! Umeed karti hoon aap theek hongay. Jab hum 'lab standards' ki baat karte hain, toh iska matlab hota hai woh substances jin ki composition aur purity humein bilkul sahi pata hoti hai. Yeh chemicals reference points ke tor par use hotay hain taake hum doosre unknown samples ki concentration ya purity ko accurately determine kar saken. Chalein, main aapko iski ek simple analogy se samjhati hoon. Imagine karein aapke paas ek measuring tape hai jis par markings bilkul sahi nahi hain. Ab agar aapko kisi cheez ki sahi lambai naapni ho, toh aap kya karengay? Aap pehle us tape ko kisi aisi cheez se compare karengay jiski lambai aapko pehle se pata ho, jaise ek standard ruler. Jab aapko pata chal jaye ga ke aapki tape kitni ghalat hai, toh aap us hisaab se apni measurements ko adjust kar saken gay. Bilkul isi tarah, chemistry lab mein bhi humein 'standard substances' ki zaroorat hoti hai. Yeh woh 'standard rulers' hotay hain jin se hum apne doosre solutions ya chemicals ki strength ya concentration ko compare karte hain. Kya yeh analogy aapko samajh aayi?