Internal table declaration in sap abap with example program

PROGRAM demo_internal_table.

TYPES: BEGIN OF mytext,
         number TYPE i,
         name(10) TYPE c,
       END OF mytext.

TYPES mytab TYPE STANDARD TABLE OF mytext WITH DEFAULT KEY.

DATA text TYPE mytext.
DATA itab TYPE mytab.

text-number = 1. text-name = 'John'.
APPEND text TO itab.
text-number = 2. text-name = 'Paul'.
APPEND text TO itab.
text-number = 3. text-name = 'Ringo'.
APPEND text TO itab.
text-number = 4. text-name = 'George'.
APPEND text TO itab.

LOOP AT itab INTO text.
  WRITE: / text-number,text-name.
ENDLOOP.