1.2 Compare and contrast fundamental data types and their characteristics

📘CompTIA ITF+ (FC0-U61)

What Is a Boolean?

A Boolean is a data type that can store only one of two possible values:

TRUE (sometimes written as True, 1, or On)
FALSE (sometimes written as False, 0, or Off)

These two values represent binary logic, which computers use to make decisions.

Why Is the Boolean Type Important?

Booleans allow systems and programs to make logical choices such as:

Should a feature be enabled or disabled?
Is a user allowed access?
Has a condition been met?
Does a device respond with a success or failure?

Booleans are used to control actions, test conditions, and determine flow in programs and systems.

Characteristics of Boolean Data Type

✔ Stores only two values

A Boolean cannot hold numbers, words, or characters.
It is strictly true/false, yes/no, on/off, or 1/0.

✔ Used for decision-making

Programs read Boolean values to decide what to do next.

Example in programming logic:

if (isLoggedIn == true):
    allow access
else:
    show login screen

✔ Very memory-efficient

It requires very little storage because storing only two values is simple for a computer.

✔ Used in conditions and comparisons

Boolean results often come from comparison operations, such as:

5 > 3 → TRUE
5 == 10 → FALSE
passwordEntered == correctPassword → TRUE or FALSE

How Booleans Are Used in IT (Exam-Relevant Examples)

Below are simple, IT-related examples (no non-IT real-world objects).

1. Login Systems (Authentication)

When a user tries to log in, the system checks:

Is the username valid? → TRUE/FALSE
Is the password correct? → TRUE/FALSE
Is the account active? → TRUE/FALSE

If any of these checks return FALSE, access is denied.

This is Boolean logic in action.

2. Network Configuration

Booleans are used in network device settings, such as:

DHCP enabled: TRUE/FALSE
Firewall enabled: TRUE/FALSE
Wi-Fi broadcasting: TRUE/FALSE

Each setting turns a feature on or off.

3. Security Settings

Security tools use Boolean flags to control behavior:

Antivirus real-time protection: ON/OFF
User has admin privileges: TRUE/FALSE
File is digitally signed: TRUE/FALSE

These Boolean values decide whether certain security actions are allowed.

4. System Monitoring

System health checks return Boolean results such as:

Is the server online? TRUE/FALSE
Is the disk space above the minimum requirement? TRUE/FALSE
Has a backup completed successfully? TRUE/FALSE

Booleans help automate alerts and actions.

5. Programming and Automation Scripts

In automation scripts (like PowerShell, Bash, or Python), Booleans decide what the script should do next.

Example (easy to understand):

serviceRunning = true

if serviceRunning:
    print("System operating normally")
else:
    print("Service stopped. Restart required.")

Booleans drive the logic behind the script.

6. Database Fields

Databases often include Boolean fields:

is_active
has_2FA
is_verified
email_sent

These store TRUE/FALSE values for quick checks.

7. Software Application Settings

Apps often include Boolean options such as:

Dark mode: TRUE/FALSE
Notifications enabled: TRUE/FALSE
Auto-update: TRUE/FALSE

These preferences are stored and applied using Boolean values.

Boolean Operators (Exam Important)

Boolean values are often combined using logical operators:

1. AND

Returns TRUE only if both conditions are true.

TRUE AND TRUE → TRUE
TRUE AND FALSE → FALSE

Example:
User must be logged in AND verified.

2. OR

Returns TRUE if at least one condition is true.

TRUE OR FALSE → TRUE

Example:
User can enter using a password OR backup code.

3. NOT

Reverses the Boolean value.

NOT TRUE → FALSE
NOT FALSE → TRUE

Example:
NOT isAdmin = regular user.

Common Boolean Exam Questions You Should Be Ready For

The ITF+ exam may ask:

✔ What values can a Boolean store?

TRUE/FALSE, 1/0, On/Off (depending on system)

✔ Which data type is used for logical decisions?

Boolean

✔ Which operator returns TRUE only when both conditions are true?

AND

✔ Identify whether a setting is Boolean:

“Wi-Fi enabled” → Boolean
“Username” → String
“Number of login attempts” → Integer

✔ Where are Booleans used in IT?

Authentication, security settings, network config, programming, etc.

Summary (Easy to Remember)

A Boolean stores only TRUE or FALSE.
Used everywhere in IT for decision-making and system control.
Works with logical operators (AND, OR, NOT).
Essential in configuration settings, security checks, programming, and automation.
Critical for understanding how computers evaluate conditions.