standard int table is general standard table, sorted int
table is work on sorted algorithm, and hashed int table for
worked on hashed algorithm

In ABAP we have two kinds of internal Tables.
1)Index Internal Tables
2)Hash Internal Tables

Again Indexed Internal tables further divided into two types
i) Standard Internal Tables
ii)Sorted Internal Tables

So Both Standard and Sorted Internal Tables Can be accessed
by Indexes. Whereas Hashed Internal Tables Can be accessed
By Only Key Fields. For Hashed Tables System automatically
maintain a Hash Algorithm to retrieve the records with one
time hit. For sorted Tables system automatically uses Binary
Search to retrieve the records. For Standard Tables System
Follows Linear Search.