What characters should be avoided when naming GIS files, folders, and map documents?

Explain why these restrictions are necessary.

$2.$ What is a file extension, and what does the computer use it for?

$3.$ Although ArcGIS Online is a good source of many types of data, what factors may interfere

with using it to compile local data for a project?

$4.$ List ways in which users of GIS and other large$-$scale software systems need to be more

careful about working with data.

$5.$ Explain the difference between a feature class and a layer. How does this difference support

the ability of users to share the same data sets?

$6.$ What does a red exclamation point next to a map layer mean? How does one fix it$?$

$7.$ Extracting subsets of a data set is easy; combining different data sets into one feature class is

difficult. Explain why.

$8.$ What is the difference between the Summary and Description fields in the Item Description?

$9.$ Explain the difference between the terms feature, feature class, feature dataset, and

geodatabase. Which of them corresponds to a shapefile?

$10.$ Explain what happens when a feature class is generalized or dissolved. What are some rea$-$

sons why it would be done?