2. Python Core Terms

Question 1

What is an “int”?

Answer 1

A data type representing whole numbers.

Question 2

What is a “float”?

Answer 2

A data type representing decimal numbers.

Question 3

What is a “str”?

Answer 3

A data type for sequences of characters (text).

Question 4

What is a “bool”?

Answer 4

A data type with two values: True or False.

Question 5

What is a “list”?

Answer 5

An ordered, mutable collection of items.

Question 6

What is a “tuple”?

Answer 6

An ordered, immutable collection of items.

Question 7

What is a “dict”?

Answer 7

A collection of key-value pairs.

Question 8

What is a “set”?

Answer 8

An unordered collection of unique items.

Question 9

What does “if” do?

Answer 9

Executes code only if a condition is true.

Question 10

What does “for” do?

Answer 10

Loops over items in a sequence.

Question 11

What does “while” do?

Answer 11

Repeats a block while a condition is true.

Question 12

What does “break” do?

Answer 12

Exits the nearest loop.

Question 13

What does “continue” do?

Answer 13

Skips to the next loop iteration.

Question 14

What does “def” do?

Answer 14

Defines a function.

Question 15

What is a parameter?

Answer 15

A variable in a function definition.

Question 16

What is an argument?

Answer 16

A value passed to a function.

Question 17

What is a lambda function?

Answer 17

An anonymous, single-expression function.

Question 18

What does “*args” do?

Answer 18

Collects extra positional arguments.

Question 19

What does “**kwargs” do?

Answer 19

Collects extra keyword arguments.

Question 20

What is the difference between local and global variables?

Answer 20

Local variables exist within functions; global variables exist throughout the program.

Question 21

What is “try” used for?

Answer 21

To attempt code that might raise an error.

Question 22

What does “except” do?

Answer 22

Catches and handles errors.

Question 23

What does “finally” do?

Answer 23

Always runs, even if there’s an error.

Question 24

What does “raise” do?

Answer 24

Manually triggers an error.

Question 25

What is a TypeError?

Answer 25

Occurs when an operation is applied to the wrong type.

Question 26

What is a ValueError?

Answer 26

Occurs when a function gets an argument of right type but wrong value.

Question 27

What is a KeyError?

Answer 27

Occurs when a dictionary key isn't found.

Question 28

What is a class?

Answer 28

A blueprint for creating objects.

Question 29

What is an object?

Answer 29

An instance of a class.

Question 30

What is "__init__"?

Answer 30

Constructor method in a class.

Question 31

What is "self"?

Answer 31

Refers to the current object instance.

Question 32

What is inheritance?

Answer 32

A way for a class to inherit methods and properties from another.

Question 33

What is encapsulation?

Answer 33

Restricting access to parts of an object.

Question 34

What is the difference between a method and a function?

Answer 34

A method is a function inside a class.

Question 35

What does "import" do?

Answer 35

Loads a module or library.

Question 36

What does "from ... import ..." do?

Answer 36

Imports specific parts of a module.

Question 37

What is the difference between standard and third-party libraries?

Answer 37

Standard comes with Python; third-party must be installed (e.g., pandas).

Question 38

What is "None" in Python?

Answer 38

Represents the absence of a value.

Question 39

What is the difference between "is" and "=="?

Answer 39

is' checks identity; '==' checks equality.

Question 40

What does "mutable" mean?

Answer 40

Can be changed after creation (e.g., lists).

Question 41

What does "immutable" mean?

Answer 41

Cannot be changed after creation (e.g., strings).

Question 42

What is indentation?

Answer 42

Whitespace that defines code blocks.

Question 43

How do you write a comment in Python?

Answer 43

Use '#' for single-line or triple quotes for multi-line comments.