Python is a beginner-friendly programming language, widely used for web development, data analysis, automation and more. Whether you're new to coding or need a quick reference, this glossary provides clear, easy-to-understand definitions of essential Python terms—listed alphabetically for quick access. From basic concepts like variables and loops to advanced topics like decorators and generators, this guide will help us navigate Python programming with confidence.

A  |  B  |  C  |  D  |  E  |  F  |  G  |  H  |  I  |  J  |  K  |  L  |  M  |  N  |  O  |  P  |  Q  |  R  |  S  |  T  |  U  |  V  |  W  |  X  |  Y  |  Z |

A:

• abc
• abs()
• acquire()
• Activation Functions
• add()
• AIOHTTP
• aenter()
• aiter()
• all()
• and
• Anaconda
• anext()
• any()
• ascii()
• any()
• API Development in Python
• append()
• apply()
• argmax()
• argmin()
• argsort()
• Arithmetic Operators
• ArithmeticError
• AttributeError
• array
• ascii()
• as
• assert
• as_integer_ratio()
• AssertionError
• Assignment Operators
• asyncio
• Asynchronous Programming
• atexit()
• Audio Processing with Python
• Automating Tasks with Python
• AttributeError
• Artificial Neural Networks (ANNs)
• await
• Argument Unpacking (*args, kwargs)

B:

• Backpropagation in Neural Networks
• Base64 Encoding and Decoding (base64 module)
• BeautifulSoup (Web Scraping)
• bdb (Python Debugger Framework)
• Bellman-Ford Algorithm (Graph Algorithm in Python)
• Big-O Notation
• Binary Files Handling in Python
• Binary Heap (Heap Data Structure in Python)
• Binary Operations (bin(), bitwise operators, etc.)
• Binary Search
• Binary Search Trees (BST) in Python
• Binding Functions in Tkinter
• Blockchain Development with Python
• BlockingIOError
• Bokeh (Data Visualization in Python)
• Breadth-First Search (BFS) Algorithm
• break
• breakpoint()
• BrokenPipeError
• Building APIs with Django & Flask
• Building Chatbots in Python
• BufferError
• bin()
• bytearray
• bool()
• bytes()
• binascii
• bisect
• bool() function
• BytesWarning
• bytes.fromhex()

C:

• calendar module
• callable()
• capitalize()
• casefold()
• ceil()
• ChainMap (collections)
• Chatbots with Python
• Chi-Square Test in Python
• Choice() (random module)
• chr()
• classmethod
• class
• clear()
• CNN (Convolutional Neural Networks)
• collect()
• collections
• colorama (Library for Terminal Colors)
• compile()
• complex
• comprehensions
• Concurrency in Python
• copy()
• contextlib Module
• continue
• context managers
• Counter (collections module)
• count()
• covariance()
• coroutine
• cProfile
• Creating APIs with Flask
• Creating Custom Exceptions
• Creating Virtual Environments
• CSV File Handling
• cycle() (itertools)

D:

• dataclasses
• datetime (Module for Date & Time Manipulation)
• deepcopy()
• defaultdict (collections module)
• def
• del
• delattr()
• deque (collections module)
• difference() (set operations)
• dir()
• divmod()
• docstrings
• dump() (json, pickle modules)
• Data Science with Python
• Data Visualization (Matplotlib, Seaborn)
• Data Preprocessing in Machine Learning
• Decision Trees
• debugging
• decorators
• Defining Functions
• Designing RESTful APIs in Python
• descriptors
• Detecting Faces with OpenCV
• Detecting Faces with OpenCV
• dictionary
• dict
• dict comprehension
• Difference Between is and ==
• Difference Between Python 2 and 3
• dir()
• Django
  • django models
  • django views
  • django urls
  • django templates
  • django admin
  • django ORM
• Django REST Framework
• Dunder methods
• Dynamic Typing in Python
• Dynamic Programming
• DataFrame (pandas)

E:

• elif
• else
• email Module
• encode()
• end Parameter in print()
• enumerate()
• enumerations (Enum module)
• EnvironmentError
• EOFError
• Equality Operators (==, !=)
• Error Handling in Python
• escape Characters (\n, \t, etc.)
• eval()
• Exception
• Exception Chaining (raise from)
• Exception Handling (try-except)
• exec()
• except
• Exploratory Data Analysis (EDA)
• extend() (list method)
• Encapsulation in OOP
• edge detection (OpenCV)

F:

• False
• File Handling (open(), read(), write())
• FileNotFoundError
• fillna() (pandas method)
• filter()
• filtering Data in Pandas
• finally
• find() (string method)
• findall() (re module)
• first-class functions
• flatten() (NumPy, TensorFlow, PyTorch)
• Flask
  • flask route
  • flask request
  • flask render_template
  • flask jsonify
  • flask sessions
• floor() (math module)
• flush() (sys module)
• float
• for
• format()
• formatting Strings (%, .format(), f-strings)
• f-string
• frozenset
• Functional Programming in Python
• functools
• functools.partial
• functools.lru_cache

G:

• gc
• ge()
• Generators
• generator expression
• GIL (Global Interpreter Lock)
• get() (dict method)
• getattr()
• getcwd() (os module)
• getpass (getpass module)
• getsizeof() (sys module)
• globals()
• groupby()
• gzip
• Gaussian Naive Bayes (sklearn.naive_bayes)
• Gensim (Topic Modeling & NLP)
• Graph Traversal Algorithms (BFS, DFS)
• Graph Data Structures (networkx, igraph)
• Grid Search (Hyperparameter Tuning - sklearn)
• Gunicorn (WSGI HTTP Server for Python Web Apps)
• GUI Development (Tkinter, PyQt, Kivy)

H:

• hash()
• hasattr()
• heapq
• help()
• hex()
• hmac
• html.parser
• HTTPStatus
• Hyperparameter Tuning (GridSearchCV, RandomizedSearchCV)
• Hypothesis Testing (scipy.stats, statsmodels)
• HDF5 File Handling (h5py, pandas.HDFStore)
• Histogram Plots (matplotlib, seaborn)
• Hugging Face Transformers (NLP Models)
• Hybrid Inheritance in Python (OOP)

I:

• id()
• if
• Image Processing (PIL, OpenCV)
• Immutability in Python
• import
• Inheritance (OOP Concept)
• IndexError
• input()
• inspect
• instancecheck()
• Interactive Mode in Python
• Interpreted Language (Python as an Interpreted Language)
• int
• is (Identity Operator)
• isinstance()
• issubclass()
• iter()
• Iterables and Iterators
• itertools

J:

• Jaccard Similarity (Text Similarity, NLP)
• Jacobi Method (Numerical Analysis, Linear Algebra)
• Joblib (Efficient Object Serialization)
• join()
• JSON (json module)
• Jupyter Notebook
• JWT (JSON Web Token for Authentication)

K:

• K-fold Cross Validation (Model Evaluation in ML)
• Kalman Filter (Time Series & Robotics)
• Keras (Deep Learning Library)
• KeyError
• keys()
• Kivy (Python GUI Framework)
• K-means Clustering
• K-Nearest Neighbors (KNN - Machine Learning Algorithm)
• kwargs

L:

• lambda
• len()
• linecache
• Linear Regression (Machine Learning, sklearn.linear_model)
• Linked Lists (Data Structures in Python)
• list
• list comprehension
• Load Balancing (Django, Flask Deployments)
• locals()
• logging
• Logistic Regression (Machine Learning, sklearn.linear_model)
• lru_cache()
• lstrip()
• lxml

M:

• Machine Learning with Python (scikit-learn, tensorflow, pytorch)
• Magic Methods
• map()
• math
• matplotlib.pyplot
• matplotlib.figure
• max()
• memoryview
• metaclass
• min()
• module
• MongoDB with Python (pymongo)
• Monte Carlo Simulation (Statistical Analysis)
• MRO (Method Resolution Order)
• multiprocessing
• multithreading
• Mutable vs Immutable

N:

• Naïve Bayes Classifier (Machine Learning, sklearn.naive_bayes)
• NameError
• Named Tuples (collections.namedtuple)
• Natural Language Processing (NLP with Python, spaCy, nltk)
• nested functions
• next()
• NLTK (Natural Language Toolkit)
• nonlocal
• None
• NotImplemented
• NotImplementedError
• numbers
• NumPy
  • numpy.arange
  • numpy.array / numpy.ndarray
  • numpy.broadcast
  • numpy.dot
  • numpy.linspace
  • numpy.reshape
• Numerical Integration (scipy.integrate)

O:

• object
• oct()
• OOP (Object‑Oriented Programming)
• open()
• OpenCV
• operator
• OrderedDict
• os
• os.path (File and Directory Management)
• OSError
• or
• Overloading and Overriding (Polymorphism in Python)

P:

• package
• pass
• pathlib
• pattern matching
• pdb
• PEP
• PEP 8
• pickle
• pip
• Pandas
  • pandas.DataFrame
  • pandas.Series
  • pandas.read_csv()
  • pandas.concat()
  • pandas.merge()
• parsing (argparse, json, xml.etree.ElementTree)
• polymorphism (OOP concept)
• pow()
• print()
• profile
• property
• proxy objects (weakref.proxy)
• psutil (System and Process Utilities)
• pytest
• Python
• pythonic
• PyTorch
  • torch.Tensor
  • torch.nn.Module
  • torch.autograd

Q:

• Q-Learning
• qrcode (qrcode library for generating QR codes in Python)
• queue
• queue.Queue (Thread-Safe Queues in Python)
• quit()
• Quoted Strings
• Quantum Computing with Python (qiskit)
• Quickselect Algorithm (Efficient Selection Algorithm in Python)

R:

• random
• range()
• read()
• readlines()
• recursion
• reduce()
• Regular Expressions (re module)
• repr()
• Requests (requests library for HTTP requests in Python)
• ResourceWarning
• return
• reversed()
• round()

S:

• scikit-learn
• sched (Event Scheduler in Python)
• Scrapy
• scipy
• seaborn
• self
• set
• set comprehension
• shutil (High-Level File Operations in Python)
• shelve
• slice
• slicing
• socket
• sorted()
• sortedcontainers (Efficient Sorted Data Structures Library)
• spaCy (Natural Language Processing Library)
• Speech Recognition (speech_recognition library)
• split()
• SQLAlchemy
• ssl
• stack (Data Structure in Python)
• staticmethod
• statistics
• Statsmodels (Statistical Modeling in Python)
• startswith()
• str
• string (String Operations in Python)
• strip()
• subprocess (Executing Shell Commands in Python)
• sum()
• super()
• SymPy (Symbolic Mathematics Library in Python)
• sys
• sys.argv (Command-line Arguments in Python)
• SQLite (sqlite3 module for database handling)

T:

• traceback
• tabulate (Library for Printing Tables in Python)
• TensorFlow
  • tensorflow.Graph
• • tf.function
• ternary operator
• testing
• textwrap (Text Formatting in Python)
• Threading (threading module for Multi-threading in Python)
• tkinter
• time
• timeit (Measure Execution Time of Code in Python)
• total_ordering (functools.total_ordering for Comparison Methods)
• traceback (traceback module for Exception Handling & Debugging)
• trunc()
• try/except
• tuple
• tqdm (Progress Bars for Iterations in Python)
• type()
• type hinting

U:

• urllib
• U-Net (Deep Learning Architecture for Image Segmentation)
• Unicode
• unittest (unittest module for Unit Testing in Python)
• unpack (argument unpacking)
• update()
• upper()
• urllib (urllib module for handling URLs & HTTP requests in Python)
• UUID (uuid module for generating unique identifiers)

V:

• virtualenv
• ValueError
• Variable Scope (Global, Local, Enclosing, Built-in)
• Variables
• Vectorization (Optimizing Operations using NumPy/Pandas)
• virtualenv (Third-party Virtual Environment Manager for Python)
• vstack() (Stacking Arrays Vertically in NumPy)

W:

• warnings
• Wave Module (wave – Read and Write WAV Files in Python)
• weakref
• webbrowser
• Web APIs (Consuming & Building APIs using Python, FastAPI, Flask, Django Rest Framework)
• Web Crawling (Using Scrapy, BeautifulSoup, Requests)
• Web Scraping (Using BeautifulSoup, Scrapy, Selenium)
• WebSockets (Real-time Communication in Python using Websockets Library)
• while
• with
• write()

X:

• xor()
• XML (Extensible Markup Language)
  • xml.etree.ElementTree
  • xml.sax
  • xml.dom.minidom
• xlsxwriter
• XPath (Query language for selecting nodes from XML documents)

Y:

• YAML
• yield
• yfinance (Yahoo Finance API for stock market data)
• YOLO (You Only Look Once) (Object detection framework)
• yt-dlp (YouTube video downloader library)

Z:

• ZeroDivisionError
• zip()
• zip_longest()
• zfill() (String method to pad a string with zeros)
• Zope (Web application framework)
• zlib (Compression library in Python)