Ch 5Understanding Data — Class 11 Informatics Practices, concept-first.

Every sensible decision rests on facts, and facts reach us as data. Long before the term gets a formal definition, we already live by it: a student choosing a college studies the placement record of p…

Data matters for two distinct reasons. First, human beings rely on data whenever they make decisions. Second — and this is the deeper point — when a large amount of data is processed with the help of…

Data comes from many different sources, so it arrives in many different formats. An image is a collection of pixels; a video is made up of frames; a fee slip contains a few numeric and non-numeric ent…

Before any data can be processed, it must first exist in our hands — so the very first stage of working with data is data collection.

Collecting and processing data is not the end of the story. Once we gather data and process it to get results, we do not simply throw the data away — we want to keep it for future use as well.

Data interests us because it holds valuable facts and information that feed our decision making. But there is a hurdle: looking at a vast pile of raw data, nobody can arrive at a conclusion.

A pile of raw data values, however carefully collected and stored, answers no questions on its own. To turn those values into information, they must be processed — and the very first stage of processi…

A dataset with dozens or hundreds of entries cannot be judged by staring at each value individually. A measure of central tendency solves this by condensing the whole collection into a single value th…

A single central value never tells the whole story. Two different datasets can have exactly the same mean, median or mode and yet be completely different in how their values are scattered — or, equall…

- Data refer to unorganised facts that can be processed to generate meaningful results or information. - Data can be structured or unstructured.