Location requesting involves using the geolocation API in JavaScript, and allows a website to obtain high-precision location information, usually by using the device's GPS and a combination of other sensors such as nearby Wi-Fi hotspots and cell towers. This allows websites to give you more relevant results based on your location. A hotel website might use that to automatically detect where you are and list nearby hotels. If you set your browser to deny location requests, it will simply not give your location to the website. The precision of the geolocation API can be very high, although accuracy varies.
Without location requesting, a website can still determine your approximate location based on your IP address. This is called GeoIP and cannot be avoided short of using a proxy to "change" the IP address you use. IP location info is generally very rough. Sometimes it can pinpoint the city block you live in, and other times it doesn't even get the city right. IP geolocation cannot be relied on for accuracy.
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