Indexed Buckets
A symbol is used to index a table, which provides a pointer to a linked list of symbols.
 Hashed with Buckets: 
A hashing function is used to index the table of
buckets.
| Insert: | O(1) | |
| Search: | O(n) | Actually n / (2 · nb) | 
| nb (number of buckets) can be large. | 
 Alphabetized Buckets: 
The first character of first few characters of a symbol are used to index
the table of buckets.
| Insert: | O(n) | Linked list is sorted | 
| Search: | O(n) | Actually n / (2 · nb) |