Lecture 3: Data Types, Input/Output, and Basic Functions

Vocabulary flashcards reviewing fundamental Python data types, type conversion, string formatting, standard input/output operations, and basic functions.

Data Type

A property of a variable or data value that tells the Python interpreter how to interpret the binary sequence of $1$s and $0$s stored in computer memory.

Integer

A built-in numerical data type (int) that represents whole numbers without a decimal point, which can be positive, negative, or zero (such as $1$, $2$, $100$, $0$, or $-20$).

Floating-Point Number

A built-in numerical data type (float) that represents numbers containing a decimal point, modeled in scientific notation via a Mantissa and an Exponent.

Mantissa

The component of a floating-point number represented in scientific notation containing the significant digits, assumed to have $1$ digit before the decimal point.

Exponent

The power of $10$ by which the Mantissa is multiplied when expressing a floating-point number in scientific notation (e.g., in $1234.567 = 1.234567 \times 10^3$).

Boolean

A built-in data type (bool) that can hold only one of two case-sensitive values starting with an uppercase letter: True or False.

String

A built-in data type (str) representing text, constructed from individual characters strung together and specified inside matching single (') or double (") quotation marks.

Escape Character

The backslash symbol (\) in Python, which directs the interpreter to interpret the immediately following character in a special manner rather than literally.

String Concatenation

The operation performed by the + operator when placed between two strings, which glues the strings together into a combined single string.

String Multiplication

An operation defined between a string and an integer (<string> * <int>) using the * operator that duplicates and repeats the string a specified number of times.

Truncation

The action that occurs when converting a floating-point number to an integer via int(), where any fractional portion past the decimal point is completely dropped.

repr()

A built-in Python function alternative to str() that produces a string representation of an object, preserving visible quotation marks and escape sequences when printed.

Console

The standard interface window or screen that displays output from a running Python program and receives standard user input entered via keyboard.

input()

A built-in Python function that reads a line of standard input typed by a user until the Enter key is pressed, returning the captured input strictly as a string.

print()

A built-in Python function that formats and displays literals, variables, or expressions to the console, ending the line automatically unless configured otherwise.

sep parameter

A keyword argument in the print() function (sep="<something>") that customizes the separator placed between printed items instead of the default space.

end parameter

A keyword argument in the print() function (end="<something>") that replaces the default newline character printed at the end of output.

f-string

A formatted string literal starting with f or F containing curly braces {} that evaluate embedded variables, values, or expressions directly within the string.

Format Specifier :.Xf

A syntax option used inside an f-string placeholder (e.g., {value:.5f}) that rounds and formats a floating-point value to exactly X decimal places.

Alignment Specifiers (

Formatting specifiers within f-strings or string methods used to align text within a designated width field: < for left, > for right, and ^ for center.

Banker's Rounding

The rounding strategy employed by Python's :.0f specifier where numbers residing exactly halfway between two integers round to the nearest even integer.

Function

A named block of reusable code that can be invoked using arguments, helping break complex computational problems into smaller manageable sub-tasks.

.rjust()

A string method (.rjust(width, fillchar)) that right-justifies a string within a field of designated width, padding the left side with spaces or a specified single character.

.ljust()

A string method (.ljust(width, fillchar)) that left-justifies a string within a field of designated width, padding the right side with spaces or a specified single character.

.center()

A string method (.center(width, fillchar)) that centers a string within a field of designated width, padding both sides evenly with spaces or a specified single character.