Some search engines deliver he same result no matter who is using them. However, others, notably most web serach tries to learn your interests based on previous activity and hence to prodcue more personalised results. This is clearly useful in areas such as music selction by streaing services, but mean one is rarely exposed to choices that might stretch one's musical appreciation. Similarly, for web search ths means that a search for "chihuahua" would usefully produce different results if you are a dog lover or frequent traveller. the downside is that this personalisation can lead to filter bubbles and exacerbate extreme views.
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