Neural Network Architecture: Types, Components & Key Algorithms

By upGrad

Updated on Nov 20, 2025 | 19 min read | 69.98K+ views

Share:

Neural network architecture defines how an AI model processes information through layers, connections, and learning rules. It shapes how data moves, how features are extracted, and how final outputs are generated. The structure decides the model’s speed, accuracy, and suitability for tasks like vision, language, or sequence mapping. Every choice in the design influences how well the system learns and generalizes.

In this guide, you’ll read more about what neural network architecture means, the key components that drive learning, the main types of neural networks, core algorithms used in training, real-world applications, design best practices, and the latest trends shaping modern AI models.

Do you want to unlock career-defining opportunities with cutting-edge tech? Check out our Artificial Intelligence Courses from top universities and get started with your upskilling journey!

Overview of Neural Network Architecture

Neural network architecture is the blueprint that explains how an artificial neural network is built and how it works.

Let's understand it by diagram below.

How Neural Network Architecture Works

A neural network processes information step by step. The flow is easy to follow once you break it down:

  • Data enters through the input layer.
  • It moves through one or more hidden layers.
  • Each layer performs matrix operations using weights and bias.
  • An activation function shapes the signal before passing it on.
  • The output layer gives the final prediction.
  • Backprop adjusts weights to reduce errors.

This repeated cycle allows the model to learn from data and improve over time.

Also Read: Biological Neural Network and Artificial Neural Networks: Key Differences, Applications, and More

Key Elements That Shape the Architecture

Several factors decide how strong or flexible the architecture becomes:

  • Depth: Total number of layers.
  • Width: Number of nodes in a layer.
  • Activation choice: How signals transform.
  • Connection pattern: How layers talk to each other.
  • Flow direction: Whether data moves forward only or loops back, like in sequence models.

Each element adds its own role. Together, they create a complete structure that allows the network to learn patterns in images, text, sound, and numerical data.

Also Read: Neural Network Model: Brief Introduction, Glossary & Backpropagation

Common Components and Their Purpose

Here is a simple table that shows the basic parts of a neural network:

Component

Role

Input layer Receives the raw data
Hidden layers Extract features and patterns
Output layer Produces the final result
Weights Control signal strength
Bias Adjusts output before activation
Activation function Adds non-linearity
Loss function Measures prediction error

These components work as a single system. The architecture defines how they connect and interact.

Also Read: AI Tutorial Made Simple: Learn Artificial Intelligence from Scratch

Types of Neural Networks

There are several types of neural networks, and each one follows a different neural network architecture depending on the task it aims to solve. The structure, data flow, and learning style vary from model to model. Understanding these types helps you select the right architecture of neural network for images, text, sequences, and generative tasks.

Below are the most common and widely used types of neural networks in modern AI systems.

Feedforward Neural Networks (FNN)

This is the simplest neural network architecture.
Data moves in a straight path from the input layer to the output layer.
There is no memory of past steps or feedback loops.

FNNs are useful for:

They serve as the foundation for more advanced network designs.

Also Read: Understanding What is Feedforward Neural Network: Detailed Explanation

Convolutional Neural Networks (CNN)

CNNs use a specialized neural network architecture built for spatial and image-based data.
They scan images with filters to detect edges, textures, shapes, and other details.

Common uses include:

Their strength lies in capturing local and global features with high accuracy.

Also Read: Beginner’s Guide for Convolutional Neural Network (CNN)

Recurrent Neural Networks (RNN)

RNNs handle sequence data.
They maintain small memories of past inputs, making them suitable for tasks where order matters.

Used for:

  • Text sequences
  • Speech recognition
  • Time-series data
  • Signal analysis

This neural network architecture can struggle with long sequences, leading to advanced forms like LSTM and GRU.

Also Read: Recurrent Neural Networks: Introduction, Problems, LSTMs Explained

LSTM and GRU Networks

LSTM and GRU networks manage long-term information more effectively.
They solve the memory issues found in standard RNNs.

They work well for:

  • Language modelling
  • Translation
  • Chat and voice systems
  • Long time-series patterns

These models capture context across many steps.

Autoencoders

Autoencoders learn to compress input data and reconstruct it.
This type of neural network architecture focuses on reducing noise and extracting key features.

Used for:

They help simplify large datasets while keeping important information.

Generative Adversarial Networks (GANs)

GANs contain two networks that learn by competing with each other.
One generates content while the other evaluates it.

Best suited for:

  • Image generation
  • Style transformation
  • Synthetic data
  • Creative tasks

GANs are known for producing realistic outputs that look human-made.

Also Read: The Ultimate Guide to Gen AI Tools for Businesses and Creators

Transformers

Transformers apply attention-based learning.
Instead of processing data step by step, they focus on the most important parts at once.

Used in:

This neural network architecture is powerful for long and complex sequences.

Also Read: The Evolution of Generative AI From GANs to Transformer Models

Hybrid Neural Networks

Hybrid networks combine multiple types of neural networks to improve results.
For example, CNN layers may extract image features, and RNN layers may handle sequence order.
Transformers may be paired with convolution blocks for vision tasks.

They offer flexibility when a single method is not enough.

Quick Comparison Table

Neural Network Type

Best For

FNN Simple prediction tasks
CNN Image and spatial data
RNN Sequence-based input
LSTM/GRU Long-term sequence patterns
Autoencoder Compression and reconstruction
GAN Generated content
Transformer Long text and complex sequences

These types of neural networks form the core structures used in today’s AI systems. Each neural network architecture brings its own strengths, and the right choice depends on your data and the outcome you want to achieve.

Also Read: Artificial Neural Networks Explained

Machine Learning Courses to upskill

Explore Machine Learning Courses for Career Progression

360° Career Support

Executive PG Program12 Months
background

Liverpool John Moores University

Master of Science in Machine Learning & AI

Double Credentials

Master's Degree18 Months

Neural Network Learning Process

The neural network learning process explains how a model studies data, adjusts its internal structure, and improves its predictions over time. Every neural network architecture follows the same core idea: it learns by comparing its output with the correct answer and then correcting itself. This cycle repeats many times until the model becomes accurate and stable.

The learning process has a few essential steps. Each step plays its own role, and together they help the model understand patterns in numbers, text, images, or sequences.

Forward Propagation

Forward propagation is the first stage.
The network receives input and pushes it through every layer.

Here is how it works:

  • The input layer takes the raw data.
  • Hidden layers apply weights, bias, and activation functions.
  • Each transformation extracts a deeper feature from the previous step.
  • The output layer gives the final prediction.

This stage shows how the chosen architecture of neural network handles information flow.

Also Read: Deep Learning Tutorial for Beginners

Loss Calculation

After generating an output, the model compares it with the real answer.
The difference is the loss.
A high loss means the prediction is far from correct.

Common loss functions include:

Loss Type

Use Case

Mean squared error Regression tasks
Cross-entropy Classification
Binary cross-entropy Two-class problems

The loss acts as a signal that tells the network how much it must improve.

Also Read: What Is Entropy in Machine Learning? Meaning, Formula, and ML Use Cases

Backpropagation

Backpropagation moves the error backward through the network.
It finds out which weights and nodes contributed to the mistake.

In simple terms:

  • The algorithm tracks how each layer affected the loss.
  • It calculates gradients for all parameters.
  • These gradients show the direction of improvement.

This step is the heart of the neural network learning process.

Weight Updates

Once the gradients are ready, the optimizer updates the weights.

The most common optimizers are:

Each method adjusts the weights in a slightly different way, but the goal is the same: reduce the loss and make the model learn patterns more accurately.

Also Read: Understanding Stochastic Gradient Descent in Machine Learning: A Beginner’s Guide

Training Cycle

The full learning cycle repeats for many rounds, called epochs.
With each round, the model becomes better at understanding the data.
Over time, the neural network architecture turns raw inputs into reliable predictions.

This process is what allows neural networks to learn from examples rather than following fixed rules.

Comparing Neural Network Architectures

Different neural network architectures solve different problems, and each design comes with its own strengths and trade-offs. Comparing these architectures helps you understand how they behave, how they process information, and when each one should be used.

Below is a clear, beginner-friendly breakdown of the most common architectures you will see in practice.

Feedforward Neural Networks vs Convolutional Neural Networks

FNNs follow a simple, straight data path.
CNNs use filters and feature maps to capture patterns in images and spatial data.

Feature

Feedforward Neural Network

Convolutional Neural Network

Data flow Forward only Forward with feature extraction
Best for Simple prediction tasks Images and spatial patterns
Key strength Easy structure Strong feature detection
Limitation Weak with complex inputs Not suited for long sequences

CNNs vs Recurrent Neural Networks

CNNs focus on spatial detail.
RNNs focus on ordered data where past steps matter.

Feature

CNN

RNN

Input type Images, grids Text, audio, sequences
Data handling Local pattern extraction Memory of previous steps
Best use Vision tasks Time-based tasks
Limitation No sense of order Hard to learn long patterns

Also Read: CNN vs. RNN: Key Differences and Applications Explained

RNN vs LSTM vs GRU

RNNs struggle with long-term information.
LSTM and GRU fix this issue with improved memory control.

Feature

RNN

LSTM

GRU

Memory strength Low High Medium–high
Training speed Fast Slower Faster
Best use Short sequences Long sequences Balanced tasks
Limitation Forgetfulness Heavy structure Limited flexibility

Also Read: Guide to CNN Deep Learning

Autoencoders vs GANs

Both learn from data, but for different reasons.
Autoencoders compress and rebuild.
GANs generate new content.

Feature

Autoencoder

GAN

Purpose Compression Creation
Output Reconstructed input New data
Best use Noise removal Image generation
Limitation Blurry outputs Training instability

Transformers vs RNN-based Models

Transformers changed how modern AI handles sequences.
They use attention instead of step-by-step processing.

Feature

Transformer

RNN/LSTM/GRU

Processing style Parallel with attention Sequential
Speed Fast at scale Slower
Best for Long text, large models Short to medium sequences
Limitation High resource demand Struggles with long context

Also Read: Explore 8 Must-Know Types of Neural Networks in AI Today!

Hybrid Neural Network Architectures

Some tasks need a mix of methods.
Hybrids blend two or more architectures to balance strengths.

Common mixes include:

  • CNN + RNN
  • Transformer + CNN
  • Autoencoder + GAN

Hybrid Type

Use Case

CNN + RNN Video and action recognition
Transformer + CNN Vision tasks with global context
Autoencoder + GAN Clean yet realistic data generation

Comparing these architectures helps you understand why models behave differently and why the right neural network architecture matters for every project. Each design brings a unique way of handling data, and choosing the correct one depends on the problem you want the model to solve.

Also Read: Explaining 5 Layers of Convolutional Neural Network

Real-World Applications of Neural Networks

Neural networks appear in many of the tools you use every day. Their flexible neural network architecture allows them to understand images, text, speech, numbers, and even real-time signals. Different types of neural networks support different tasks, and each one helps solve problems that traditional methods struggled with.

Below are some of the most common real-world uses.

Image and Vision Tasks

Neural networks play a major role in visual recognition.
CNN-based architecture is especially strong at identifying patterns in pixel data.

Common uses include:

  • Image classification
  • Medical imaging
  • Object and face detection
  • Quality inspection in manufacturing

These models help systems understand visual scenes with high accuracy.

Also Read: Face Detection Project in Python: A Comprehensive Guide for 2025

Speech and Audio Processing

Networks can identify patterns in sound waves and convert them into meaningful outputs.

You will see them in:

  • Voice assistants
  • Speech-to-text tools
  • Emotion detection
  • Noise reduction systems

RNNs, GRUs, LSTMs, and transformers all contribute to these tasks.

Also Read: Top 10 Speech Processing Projects & Topics You Can’t Miss in 2025!

Natural Language Processing

Text requires a neural network architecture that understands context, grammar, and patterns in sequences.

Applications include:

Transformers have become the standard for long and complex text.

Healthcare and Diagnostics

Neural networks help doctors make data-driven decisions.
They identify subtle patterns that may be hard for humans to spot.

Used for:

  • Predicting disease risks
  • Reading scans
  • Treatment planning
  • Monitoring patient trends

Their accuracy supports early detection and prevention.

Finance and Business Forecasting

Numbers and time-series data fit well with many types of neural networks.

Some uses include:

  • Stock trend analysis
  • Fraud detection
  • Credit scoring
  • Demand forecasting

These models analyze patterns and support better decision-making.

Also Read: AI in Banking and Finance Explained: Trends, Uses, & Impact

Autonomous Systems

Self-driving vehicles and robotics depend heavily on neural networks.

They support:

  • Object tracking
  • Route prediction
  • Motion control
  • Scene understanding

These systems rely on fast, reliable pattern recognition.

Neural networks have become a core part of modern technology. Their ability to learn from examples and adapt to different kinds of data makes them valuable in almost every industry today.

Also Read: Machine Learning Algorithms Used in Self-Driving Cars: How AI Powers Autonomous Vehicles

Subscribe to upGrad's Newsletter

Join thousands of learners who receive useful tips

Promise we won't spam!

Implement Neural Networks Using Python

Python is the most accessible way to work with any neural network architecture. Its clean syntax and strong libraries make it easy for beginners to build, train, and test models without dealing with complex math directly. You only need a basic understanding of arrays, loops, and functions to get started. From small feedforward networks to deeper models, Python offers ready-made tools that help you focus on learning rather than setup.

Most implementations follow the same steps.
You load data, prepare it, choose a model, train it, and test the results. Popular libraries like TensorFlow and PyTorch provide simple functions that handle the details of weight updates, activation functions, and layers.

Common Python Libraries for Neural Networks

You will work mostly with:

  • NumPy for arrays and math
  • TensorFlow for flexible model creation
  • Keras for quick and clean model building
  • PyTorch for dynamic computation and research-style work
  • Scikit-learn for basic tasks and data tools

These libraries support different types of neural networks, from simple feedforward models to CNNs, RNNs, and transformers.

Example: Simple Neural Network in Keras

This example shows how a basic model looks in Python:

from tensorflow.keras.models import Sequential
from tensorflow.keras.layers import Dense

model = Sequential()
model.add(Dense(16, activation='relu', input_shape=(10,)))
model.add(Dense(8, activation='relu'))
model.add(Dense(1, activation='sigmoid'))

model.compile(optimizer='adam', loss='binary_crossentropy', metrics=['accuracy'])
model.fit(X_train, y_train, epochs=10)

Expected Output:

Epoch 1/20
100/100 [==============================] - 1s 5ms/step - loss: 0.6882 - accuracy: 0.5480
Epoch 2/20
100/100 [==============================] - 0s 3ms/step - loss: 0.6621 - accuracy: 0.6040
Epoch 3/20
100/100 [==============================] - 0s 3ms/step - loss: 0.6314 - accuracy: 0.6500
Epoch 4/20
100/100 [==============================] - 0s 3ms/step - loss: 0.5983 - accuracy: 0.6900
Epoch 5/20
100/100 [==============================] - 0s 3ms/step - loss: 0.5632 - accuracy: 0.7200
Epoch 6/20
100/100 [==============================] - 0s 3ms/step - loss: 0.5305 - accuracy: 0.7450
Epoch 7/20
100/100 [==============================] - 0s 3ms/step - loss: 0.5037 - accuracy: 0.7620
Epoch 8/20
100/100 [==============================] - 0s 3ms/step - loss: 0.4796 - accuracy: 0.7800
Epoch 9/20
100/100 [==============================] - 0s 3ms/step - loss: 0.4567 - accuracy: 0.7920
Epoch 10/20
100/100 [==============================] - 0s 3ms/step - loss: 0.4380 - accuracy: 0.8040

This structure can change based on your task. You can add more layers, switch activation functions, or use a different neural network architecture depending on the data.

Comparison of Model Choices

Task Type

Suggested Architecture

Images CNN
Text and sequences RNN or transformer
Simple prediction Feedforward network
Compression Autoencoder

Python lets you mix and match these designs with minimal code changes.

Also Read: A Guide to Linear Regression Using Scikit [With Examples]

Why Python Works Well for Neural Networks

  • It supports easy experimentation
  • Most research papers share Python code
  • Large community support
  • Quick model testing with fewer steps
  • Smooth integration with data tools like Pandas

With these advantages, Python remains the most practical path for learners who want hands-on experience with neural networks. Whether you explore CNNs, RNNs, GANs, or transformers, Python gives you everything you need to learn, build, and refine your models.

Conclusion 

Neural network architecture is about to enter a new era where intelligence and creativity come together in exciting ways. Inspired by the workings of a biological neural network, future neural networks won’t just process data, they’ll understand context, provide new insights, and work alongside humans to solve major global problems.

If you want to build a career in neural networks, upGrad’s courses will give you a strong understanding of the topic, combining essential theory with practical, hands-on experience.

Here are some courses offered by upGrad in neural networks and machine learning.

Do you need help deciding which course to take to advance your career in machine learning? Contact upGrad for personalized counseling and valuable insights.

Similar Reads:

Frequently Asked Questions

1. What is a neural network architecture?

Neural network architecture is the structure that defines how data moves through layers, how connections work, and how the model learns. It explains the role of each layer and how they combine to produce predictions across tasks like vision, text, and time-series.

2. Why is the architecture of neural network models important?

The architecture of neural network models shapes how well a system learns patterns. It affects accuracy, training time, and the kind of data the model can handle. A well-designed structure helps the model extract features smoothly and make stable predictions.

3. What are the main types of neural networks used today?

The main types of neural networks include feedforward models, CNNs, RNNs, LSTMs, GRUs, transformers, autoencoders, and GANs. Each type handles different data formats, making them useful for images, text, speech, sequences, or generating new data.

4. How does a neural network architecture diagram help beginners?

A neural network architecture diagram shows the model’s flow step by step. It makes layers, inputs, outputs, and connections easy to see. This visual guide helps beginners understand how signals move and how each layer contributes to the final prediction.

5. What components make up a basic neural network architecture?

A basic neural network includes an input layer, hidden layers, an output layer, activation functions, weights, bias, and a loss function. These components work together to turn raw input into meaningful output through repeated learning cycles.

6. How do activation functions influence a model?

Activation functions decide how signals transform inside layers. They let the network learn complex patterns by controlling which values move forward. Without them, the model would only learn simple relationships and fail to detect deeper features.

7. What is the difference between shallow and deep architectures?

Shallow architectures use a small number of layers and work well for simple tasks. Deep architectures use many layers to extract detailed features, making them better for images, text, and large datasets. Depth increases learning capacity but also training needs.

8. How do weights and bias affect predictions?

Weights control the strength of each connection, while bias adjusts the signal before activation. Together, they determine how strongly each input influences the outcome. Training updates these values to reduce errors and improve accuracy.

9. What role does backpropagation play in neural network learning?

Backpropagation calculates errors after each prediction and sends them backward through the network. This helps adjust weights and bias in a direction that reduces mistakes. It is the main method that lets models refine themselves over time.

10. How do optimizers improve training?

Optimizers control how weights update during training. Methods like SGD, Adam, and RMSProp adjust learning steps to improve stability and speed. A good optimizer prevents slow training and helps the model reach accurate results faster.

11. When should you use a convolutional neural network?

Use a convolutional neural network when working with images or spatial data. CNNs scan small regions, pick up patterns like edges and textures, and combine them into larger features. This makes them effective for tasks such as classification and detection.

12. When is an RNN or LSTM a better choice?

RNNs and LSTMs work well when order matters, such as in text, speech, time-series, and sensor data. They maintain context across steps, helping the model understand sequences and long-term patterns that simpler structures cannot manage.

13. How do transformers differ from earlier neural networks?

Transformers use attention instead of step-by-step processing. They look at all input positions at once, making them effective for long text and large datasets. This design improves speed, context handling, and overall performance in language tasks.

14. What is the role of an autoencoder?

An autoencoder reduces data by compressing it into a smaller form and then rebuilding it. This helps remove noise, simplify features, and extract useful patterns. Autoencoders are used in compression, reconstruction, and feature learning tasks.

15. How do GANs generate new data?

GANs use two linked networks: one creates new samples while the other checks if they look real. Through continuous learning, the generator improves its output, leading to realistic images, audio, or synthetic examples for creative and analytical tasks.

16. How can a neural network architecture be improved?

Improving a neural network architecture involves adjusting layers, choosing better activation functions, tuning hyperparameters, applying regularization, and using stronger optimizers. Testing different designs helps find the best fit for your dataset.

17. What causes overfitting in neural networks?

Overfitting happens when a model learns noise instead of real patterns. This occurs when the network is too complex or the dataset is too small. Techniques like dropout, early stopping, and data augmentation help reduce this issue.

18. How do you choose the right neural network architecture for a project?

Choose an architecture based on data type and problem complexity. CNNs suit images, RNNs suit sequences, transformers suit long text, and feedforward networks suit simpler tasks. Testing a few small versions helps confirm the right match.

19. What tools help create a neural network architecture diagram?

Tools like TensorBoard, Netron, Lucidchart, and draw.io help create a clear neural network architecture diagram. These tools show each layer, its parameters, and the flow of data, making the model easier to understand and debug.

20. What industries rely most on neural networks today?

Neural networks are used in healthcare, finance, retail, transportation, security, and entertainment. They support prediction, diagnosis, forecasting, recognition, automation, and real-time decision-making across many modern systems.

upGrad

569 articles published

We are an online education platform providing industry-relevant programs for professionals, designed and delivered in collaboration with world-class faculty and businesses. Merging the latest technolo...

Speak with AI & ML expert

+91

By submitting, I accept the T&C and
Privacy Policy

India’s #1 Tech University

Executive Program in Generative AI for Leaders

76%

seats filled

View Program

Top Resources

Recommended Programs

LJMU

Liverpool John Moores University

Master of Science in Machine Learning & AI

Double Credentials

Master's Degree

18 Months

IIITB
bestseller

IIIT Bangalore

Executive Diploma in Machine Learning and AI

360° Career Support

Executive PG Program

12 Months

upGrad
new course

upGrad

Advanced Certificate Program in GenerativeAI

Generative AI curriculum

Certification

5 months