The Basic Start-Up Screen; The Basic Prompt - IBM 5150 Manual To Operations

The BASIC Start-up Screen
When BASIC is started, a screen similar to this is
displayed:
The IBM Personal Computer Basic
Version Dl.00 Copyright IBM Corp. 1981
Bytes free
The cursor is here.
The D in this message tells you that Disk BASIC has been
started. The message may instead show a C for Cassette
BASIC, or an A for Advanced BASIC.
Instead of xxxxx, you will see some number that tells
you how much room you have in the computer's
r"\
memory for your programs and data.
The BASIC Prompt
Ok is BASIC's prompt. It tells you that BASIC is ready
for you to tell it what to do. You need to remember to
type BASIC commands and statements after Ok-you
can use DOS commands only when you see A>; not
when you see Ok.
Ok also tells you that the keyboard is operating in
BASIC mode. Look in "Keyboard Layout and Usage"
for a complete description of what the keys do.
BASIC 3-6