Below is a jpg image of Indiana, Ohio, and Illinois.
The projection I selected is WGS-1984 coordinate system with a Mercator projection. I chose this because I am not mapping a large region, just a few states. Since it's a small area, I wouldn't have to worry about much distortion; and the counties are very well distributed. The WGS-1984 is a reference coordinate system used by the Global Positioning System. If I will be discussing popular locations in these states, using the WGS will allow people to accurately use their GPS's while visiting the attractions.
Definitions pertaining to this exercise:
- .xls file: Excel file
- select by attributes: making a selection based on certain attributes in a field; allows you to provide a SQL query expression that is used to select features that match the selection criteria
- query: a request to select features or records from a database
- fields (in a table): a column in a table that stores the values for a single attribute
- records (in a table): the rows in a table that stores information for an attribute
- attributes: nonspatial information about a geographic feature in GIS, usually stored in a table and linked to a feature by a unique identifier
- relational database: a database structured to recognize relations among stored items of information
- join function: appending the fields of one table to those of another through an attribute or field common to both tables
- calculate/field calculator: tool that allows you to perform a calculation based on different fields in the attribute table; for example, length, and area can also be calculated.
*all definitions taken from the ESRI software dictionary
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