Question

Differentiate between raster and vector data models.

Answer 1

Raster data represents a graphic feature as a pattern of grids of squares, whereas vector data represents the object as a set of lines drawn between specific points.

Answer 2

Sr. No.	Feature	Raster data model	Vector data model
1.	Structure	In the raster data model, data is represented using a grid of rows and columns where each cell or pixel holds a value.	In the vector data model, data is represented using points, lines, and polygons based on coordinate pairs.
2.	Representation	The raster model represents continuous data such as elevation, temperature, or satellite images.	The vector model represents discrete data such as roads, rivers, and administrative boundaries.
3.	Precision	The precision of raster data depends on the cell size or resolution, with smaller cells providing more detail.	The vector model provides high precision because each feature is defined by exact coordinates.
4.	Storage and Size	Raster data requires large storage space, especially for high-resolution images or detailed data.	Vector data generally requires less storage space, particularly for discrete and well-defined features.
5.	Data type	Raster data is ideal for continuous spatial phenomena, where changes occur gradually across an area.	Vector data is ideal for discrete features that have specific boundaries or linear shapes.
6.	Examples	Examples of raster data include digital elevation models (DEMs), scanned maps, and satellite images.	Examples of vector data include road maps, river networks, land parcel boundaries, and utility lines.
7.	Use in GIS	Raster data is commonly used in applications that require continuous data analysis, such as environmental monitoring.	Vector data is commonly used in applications that require precision, such as cadastral mapping and transportation networks.