What is a Classification?
The task of sorting inputs into predefined categories — choosing a label rather than producing a number.
Classification explained in plain English
Classification is the task of sorting inputs into predefined categories. The system chooses a label — spam or not spam, cat or dog, positive or negative — rather than producing a number.
It is one of the most widely deployed types of machine learning in industry.
Analogy
Classification is like a post office sorting room where each letter is placed into the correct bin — local, international, express — based on what is written on the envelope.
Example
Moderation systems classify social posts as safe or violating policy; doctors use classifiers to flag suspicious moles as benign or malignant.
How is Classification used?
Email spam filters, medical diagnosis tools, sentiment analysis on product reviews, and content moderation systems all use classification to assign items to categories.
Common misconceptions about Classification
Classification outputs are probabilities or scores — a model saying "95% cat" is not the same as being certain in a human sense.
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