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Proximity Analysis Buffer Analysis Multi Buffer

 What is Proximity Analysis?

Proximity means "how close or far something is."

So, Proximity Analysis in GIS means finding out how near or far one thing is from another on a map.

 What is Buffer Analysis?

Buffer means a zone (area) around something.

In GIS:

  • If you draw a circle around a school with 1 km radius, that area is called a buffer.

  • It shows which houses or roads are within 1 km of the school.

✅ Example:
You want to find all houses within 500 meters of a river. GIS will create a buffer zone (a shaded area) around the river, and then highlight all houses inside it.

What is Multi Buffer Concept?

Instead of just one buffer zone, you can make many buffer zones around a place.

✅ Example:

Let's say you make 3 buffer zones around a hospital:

  • 0–1 km (red)

  • 1–2 km (orange)

  • 2–3 km (yellow)

Now, you can:

  • See which areas are very close (red),

  • Which are a bit far (orange),

  • And which are farther away (yellow).

This helps in emergency planning, like how quickly ambulances can reach patients.

Why is this useful?

  • For planning (e.g., building schools near homes).

  • For safety (e.g., people living near rivers or highways).

  • For environmental studies (e.g., effects of pollution around factories).

 Summary:

TermSimple Meaning
Proximity AnalysisFinding how close or far things are
Buffer AnalysisDrawing an area around a place (like a circle)
Multi BufferDrawing many zones around a place


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