Python Glossary Last Updated : 23 Jul, 2025 Comments Improve Suggest changes Like Article Like Report 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:abcabs()acquire()Activation Functionsadd()AIOHTTPaenter()aiter()all()andAnacondaanext()any()ascii()any()API Development in Pythonappend()apply()argmax()argmin()argsort()Arithmetic OperatorsArithmeticErrorAttributeErrorarrayascii()asassertas_integer_ratio()AssertionErrorAssignment OperatorsasyncioAsynchronous Programmingatexit()Audio Processing with PythonAutomating Tasks with PythonAttributeErrorArtificial Neural Networks (ANNs)awaitArgument Unpacking (*args, kwargs)B:Backpropagation in Neural NetworksBase64 Encoding and Decoding (base64 module)BeautifulSoup (Web Scraping)bdb (Python Debugger Framework)Bellman-Ford Algorithm (Graph Algorithm in Python)Big-O NotationBinary Files Handling in PythonBinary Heap (Heap Data Structure in Python)Binary Operations (bin(), bitwise operators, etc.)Binary Search Binary Search Trees (BST) in PythonBinding Functions in TkinterBlockchain Development with PythonBlockingIOErrorBokeh (Data Visualization in Python)Breadth-First Search (BFS) Algorithmbreakbreakpoint()BrokenPipeErrorBuilding APIs with Django & FlaskBuilding Chatbots in PythonBufferErrorbin()bytearraybool()bytes()binasciibisectbool() functionBytesWarningbytes.fromhex()C:calendar modulecallable()capitalize()casefold()ceil()ChainMap (collections)Chatbots with PythonChi-Square Test in PythonChoice() (random module)chr()classmethodclassclear()CNN (Convolutional Neural Networks)collect()collectionscolorama (Library for Terminal Colors)compile()complexcomprehensionsConcurrency in Pythoncopy()contextlib Module continuecontext managersCounter (collections module)count()covariance()coroutinecProfileCreating APIs with FlaskCreating Custom ExceptionsCreating Virtual EnvironmentsCSV File Handlingcycle() (itertools)D:dataclassesdatetime (Module for Date & Time Manipulation)deepcopy()defaultdict (collections module)defdeldelattr()deque (collections module)difference() (set operations)dir()divmod()docstringsdump() (json, pickle modules)Data Science with PythonData Visualization (Matplotlib, Seaborn)Data Preprocessing in Machine LearningDecision TreesdebuggingdecoratorsDefining FunctionsDesigning RESTful APIs in PythondescriptorsDetecting Faces with OpenCVDetecting Faces with OpenCVdictionarydictdict comprehensionDifference Between is and ==Difference Between Python 2 and 3dir()Djangodjango modelsdjango viewsdjango urlsdjango templatesdjango admindjango ORMDjango REST FrameworkDunder methodsDynamic Typing in PythonDynamic ProgrammingDataFrame (pandas)E:elifelseemail Moduleencode()end Parameter in print()enumerate()enumerations (Enum module)EnvironmentErrorEOFErrorEquality Operators (==, !=)Error Handling in Pythonescape Characters (\n, \t, etc.)eval()ExceptionException Chaining (raise from)Exception Handling (try-except)exec()exceptExploratory Data Analysis (EDA)extend() (list method)Encapsulation in OOPedge detection (OpenCV)F:FalseFile Handling (open(), read(), write())FileNotFoundErrorfillna() (pandas method)filter()filtering Data in Pandasfinallyfind() (string method)findall() (re module)first-class functionsflatten() (NumPy, TensorFlow, PyTorch)Flaskflask routeflask requestflask render_templateflask jsonifyflask sessionsfloor() (math module)flush() (sys module)floatforformat()formatting Strings (%, .format(), f-strings)f-stringfrozensetFunctional Programming in Pythonfunctoolsfunctools.partialfunctools.lru_cacheG:gcge()Generatorsgenerator expressionGIL (Global Interpreter Lock)get() (dict method)getattr()getcwd() (os module)getpass (getpass module)getsizeof() (sys module)globals()groupby()gzipGaussian 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()heapqhelp()hex()hmachtml.parserHTTPStatusHyperparameter 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()ifImage Processing (PIL, OpenCV)Immutability in PythonimportInheritance (OOP Concept)IndexErrorinput()inspectinstancecheck()Interactive Mode in PythonInterpreted Language (Python as an Interpreted Language)intis (Identity Operator)isinstance()issubclass()iter()Iterables and IteratorsitertoolsJ:Jaccard Similarity (Text Similarity, NLP)Jacobi Method (Numerical Analysis, Linear Algebra)Joblib (Efficient Object Serialization)join()JSON (json module)Jupyter NotebookJWT (JSON Web Token for Authentication)K:K-fold Cross Validation (Model Evaluation in ML)Kalman Filter (Time Series & Robotics)Keras (Deep Learning Library)KeyErrorkeys()Kivy (Python GUI Framework)K-means Clustering K-Nearest Neighbors (KNN - Machine Learning Algorithm)kwargsL:lambdalen()linecacheLinear Regression (Machine Learning, sklearn.linear_model)Linked Lists (Data Structures in Python)listlist comprehensionLoad Balancing (Django, Flask Deployments)locals()loggingLogistic Regression (Machine Learning, sklearn.linear_model)lru_cache()lstrip()lxmlM:Machine Learning with Python (scikit-learn, tensorflow, pytorch)Magic Methodsmap()mathmatplotlib.pyplotmatplotlib.figuremax()memoryviewmetaclassmin()moduleMongoDB with Python (pymongo)Monte Carlo Simulation (Statistical Analysis)MRO (Method Resolution Order)multiprocessingmultithreadingMutable vs ImmutableN:Naïve Bayes Classifier (Machine Learning, sklearn.naive_bayes)NameErrorNamed Tuples (collections.namedtuple)Natural Language Processing (NLP with Python, spaCy, nltk)nested functionsnext()NLTK (Natural Language Toolkit) nonlocalNoneNotImplementedNotImplementedErrornumbersNumPynumpy.arangenumpy.array / numpy.ndarraynumpy.broadcastnumpy.dotnumpy.linspacenumpy.reshapeNumerical Integration (scipy.integrate)O:objectoct()OOP (Object‑Oriented Programming)open()OpenCVoperatorOrderedDictosos.path (File and Directory Management)OSErrororOverloading and Overriding (Polymorphism in Python)P:packagepasspathlibpattern matchingpdbPEPPEP 8picklepipPandaspandas.DataFramepandas.Seriespandas.read_csv()pandas.concat()pandas.merge()parsing (argparse, json, xml.etree.ElementTree)polymorphism (OOP concept)pow()print()profilepropertyproxy objects (weakref.proxy)psutil (System and Process Utilities)pytestPythonpythonicPyTorchtorch.Tensortorch.nn.Moduletorch.autogradQ:Q-Learningqrcode (qrcode library for generating QR codes in Python)queuequeue.Queue (Thread-Safe Queues in Python)quit()Quoted StringsQuantum Computing with Python (qiskit)Quickselect Algorithm (Efficient Selection Algorithm in Python)R:randomrange()read()readlines()recursionreduce()Regular Expressions (re module) repr()Requests (requests library for HTTP requests in Python) ResourceWarningreturnreversed()round()S:scikit-learnsched (Event Scheduler in Python)Scrapyscipyseabornselfsetset comprehensionshutil (High-Level File Operations in Python)shelvesliceslicingsocketsorted()sortedcontainers (Efficient Sorted Data Structures Library)spaCy (Natural Language Processing Library)Speech Recognition (speech_recognition library)split()SQLAlchemysslstack (Data Structure in Python)staticmethodstatisticsStatsmodels (Statistical Modeling in Python)startswith()strstring (String Operations in Python)strip()subprocess (Executing Shell Commands in Python)sum()super()SymPy (Symbolic Mathematics Library in Python)syssys.argv (Command-line Arguments in Python)SQLite (sqlite3 module for database handling)T:tracebacktabulate (Library for Printing Tables in Python)TensorFlowtensorflow.Graphtf.functionternary operatortestingtextwrap (Text Formatting in Python)Threading (threading module for Multi-threading in Python)tkintertimetimeit (Measure Execution Time of Code in Python)total_ordering (functools.total_ordering for Comparison Methods) traceback (traceback module for Exception Handling & Debugging) trunc()try/excepttupletqdm (Progress Bars for Iterations in Python)type()type hintingU:urllibU-Net (Deep Learning Architecture for Image Segmentation)Unicodeunittest (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:virtualenvValueErrorVariable Scope (Global, Local, Enclosing, Built-in)VariablesVectorization (Optimizing Operations using NumPy/Pandas)virtualenv (Third-party Virtual Environment Manager for Python)vstack() (Stacking Arrays Vertically in NumPy)W:warningsWave Module (wave – Read and Write WAV Files in Python)weakrefwebbrowserWeb 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)whilewithwrite()X:xor()XML (Extensible Markup Language)xml.etree.ElementTreexml.saxxml.dom.minidomxlsxwriterXPath (Query language for selecting nodes from XML documents)Y:YAMLyieldyfinance (Yahoo Finance API for stock market data)YOLO (You Only Look Once) (Object detection framework)yt-dlp (YouTube video downloader library)Z:ZeroDivisionErrorzip()zip_longest()zfill() (String method to pad a string with zeros)Zope (Web application framework)zlib (Compression library in Python) Comment More infoAdvertise with us Next Article Company Preparation A aryantcutw Follow Improve Article Tags : Python Python Programs Python-Functions python-basics python +1 More Practice Tags : pythonpythonpython-functions Similar Reads Interview PreparationInterview Preparation For Software DevelopersMust Coding Questions - 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