373: Highlights

If you need to store information that is useful throughout your application, then you can store that information in the Smalltalk dictionary. Key–value pairs stored in the Smalltalk dictionary are often called global-variable–global-variable-value pairs.
If you want to create and assign a global variable, then instantiate the following pattern:
```
Smalltalk at: #global-variable name put: value 
```
If you want to access the value of a global variable, then use the global variable's name.

If you want to reassign a global variable, then instantiate one of the following patterns:

Smalltalk at: #global-variable name put: new value 
global-variable name := new value

If you want to create a new dictionary that is assigned to a global variable, then instantiate the following pattern:
```
Smalltalk at: #dictionary name put: Dictionary new 
```
If you want to add a new key–value entry to a dictionary, then instantiate the following pattern:
```
dictionary name at: 'key name' put: initial value 
```
If you want to know the value of a key–value entry in a dictionary, then instantiate the following pattern:
```
dictionary name at: 'key name' 
```
If you need to store information that is needed in several parts of your application, then you should store that information in a dictionary, and then you should include that dictionary in the pool dictionaries of the classes for which methods are defined that need access to the dictionary.
If you have installed a dictionary as a pool dictionary in a class, then you can set and get the values stored in that dictionary using assignment expressions to set values and keys to get values.