1. What is GIS ?

ANS : GIS, or geographic information systems, are computer-based tools used to store, visualize, analyze, and interpret geographic data. Geographic data (also called spatial, or geospatial data) identifies the geographic location of features.

These data include anything that can be associated with a location on the globe, or more simply anything that can be mapped. For example, roads, country boundaries, and address are all types of spatial data. At the CDC, we use GIS to help answer questions about how location impacts disease and disability.

2. What are the components of GIS ?

ANS:  A working GIS integrates five key components: hardware, software, data, people, and methods.

Hardware
Hardware is the computer on which a GIS operates. 

Software
GIS software provides the functions and tools needed to store, analyze, and display geographic information.

Data
Possibly the most important component of a GIS is the data. Geographic data and related tabular data can be collected in-house or purchased from a commercial data provider. 

People
GIS technology is of limited value without the people who manage the system and develop plans for applying it to real-world problems.

Methods
A successful GIS operates according to a well-designed plan and business rules, which are the models and operating practices unique to each organization.