Imagine the internet as a huge city. Every app, website, and service is like a busy shop, constantly sending and receiving packages of information. But how do all these digital “shops” know how to talk to each other? That’s where REST comes in. According to statistics and report of 2025, REST still dominates at 93%, but modern patterns are growing. Webhooks (50%) and GraphQL (33%) show that while REST remains the foundation, teams are adopting additional patterns for specific use cases like real-time communication and efficient data fetching.
REST, short for Representational State Transfer, isn’t just another tech buzzword. Basically, it’s a powerful architectural style that shapes how data moves across the internet. From sending messages to loading your favorite playlist, REST makes it possible for apps and servers to “talk” to each other in a way that’s fast, reliable, and scalable.
In this article, we’ll break down what REST is, how it works, and why it’s become the standard for building scalable and efficient web services. Let's started!
What Is REST?
In simple terms, REST is a set of principles that dictate how developers use HTTP, URLs, and Web standards. By adhering to REST principles, you can create applications that leverage the Web's architecture to your advantage.
Over the years, numerous methods have been developed to connect computers through a network using a common language. Each method or protocol addresses communication uniquely. For example, SOAP, JMS, and XML-RPC. SOAP requires large amounts of data and high computing capacity, making it unsuitable for limited application resources. JMS facilitates formal communication, mainly used in Java applications, while XML-RPC has similar issues to SOAP. Overall, these older protocols are favored by developers but can be cumbersome to use.
In contrast, REST transmits only the necessary amount of data through the same mechanism that the web uses. Basically, it avoids the problems that come with more complex protocols, enabling developers to create applications that can handle variable network speeds and limited computing capacity.
REST API Methods
REST functions similarly to how a website interacts with a browser. Developers make the resource accessible through a URL, and the program accesses that URL to retrieve the data. The two main terms to understand are resources and representations. Resources are the "things" you want to talk about, and representations refer to the "entities" you want to send.
REST (Representational State Transfer) relies on standard HTTP methods to perform operations on resources identified by URLs. A resource may represent a user, an order, a product, or any logical entity in a system. The HTTP method in the request defines the intended action.
The Main HTTP Methods
1. GET: The GET method retrieves data from the server. It does not modify the state of the resource, making it both safe and idempotent. If the same GET request is executed multiple times, it produces the same result without side effects.
2. POST: The POST method creates new resources. Unlike GET, POST modifies server state and is not idempotent. Sending the same POST request multiple times may result in multiple records being created.
3. PUT: The PUT method replaces an existing resource entirely. It requires the client to send the full representation of the resource, which the server uses to overwrite the current version.
4. DELETE: The DELETE method removes a resource from the server. It remains idempotent because after the server deletes the resource, additional DELETE requests do not change the state further.
In summary, GET, POST, PUT, and DELETE form the foundation of RESTful API design. Their correct usage ensures clear separation of responsibilities, predictable behavior, and improved reliability in distributed systems. So, understanding which methods are idempotent and which modify server state helps developers design robust retry logic and handle network failures effectively.
When implemented consistently, these methods create a clean contract between services, making integrations easier and reducing long-term maintenance complexity. Overall, for software developers building API-driven systems, mastering these four core methods is fundamental to creating scalable and reliable applications.
Benefits of REST API
For software developers building scalable SaaS solutions, REST provides a predictable, lightweight, and flexible communication model. Below are the key benefits that make REST a strong foundation for scalable software systems and why it remains the preferred architectural style for API-driven development:
1. Simplicity and Ease of Implementation
REST relies on standard HTTP methods and URLs. There is no need for complex messaging envelopes or additional transport layers. Developers can use existing HTTP infrastructure, frameworks, and libraries. Because REST follows predictable conventions, onboarding new engineers becomes faster. Generally, SaaS teams spend less time understanding integration logic and more time delivering product features.
2. Scalability
REST promotes a request-driven communication model where each interaction between client and server is independent. Also, this approach reduces server-side complexity and allows horizontal scaling. Load balancers, CDNs, and caching layers work naturally with RESTful APIs. As traffic grows, infrastructure can scale without rewriting the API architecture. For SaaS products handling thousands of concurrent requests, this characteristic becomes a major operational advantage.
3. High Performance Through Caching
REST supports HTTP caching mechanisms out of the box. Responses can be marked as cacheable, reducing unnecessary server calls. This leads to:
- Lower latency;
- Reduced server load;
- Improved user experience.
For read-heavy systems, such as product catalogs, order histories, or analytics dashboards, caching significantly optimizes performance.
4. Platform and Language Independence
REST APIs exchange data typically in JSON or XML formats. Basically, these formats are language-agnostic and widely supported. This ensures:
- Easy integration between different systems;
- Compatibility with web and IoT clients;
- Flexibility in backend technology choices.
5. Clear Resource-Oriented Structure
REST organizes data around resources (e.g., /orders, /products, /customers). Each resource has a unique URI and can be manipulated using HTTP methods. This resource-driven model creates:
- Clear API contracts;
- Predictable endpoint structure;
- Easier documentation and maintenance.
Developers can quickly understand how to interact with the system based on naming conventions alone.
6. Improved Reliability
Because REST uses standard HTTP semantics, it benefits from well-defined behavior:
- GET requests are safe and do not modify data;
- PUT and DELETE operations are idempotent;
- Status codes clearly communicate outcomes.
Eventually, this makes error handling, retries, and debugging more manageable in distributed systems.
Drawbacks of REST
Although REST API architecture offers significant benefits, it also has limitations that software developers should consider when designing scalable systems. So, understanding the drawbacks of REST helps teams choose the right architecture for their specific use case:
- Design limitations: REST has restrictions related to multiple requests over a single TCP connection and large HTTP request headers, which can slow down page loading. Additionally, the flexibility of REST APIs can sometimes make them challenging to manage.
- Stateless applications: REST does not store state information between request-response cycles, which complicates updates that don’t involve client-side polling.
- Definition: REST lacks a single reference implementation, making it difficult to measure whether a design is truly RESTful.
- Data overfetching/underfetching: RESTful services may return large volumes of unnecessary data, causing delays in data retrieval.
What is an Example of a REST API?
API2Cart is a modern REST API that enables seamless connection between multiple eCommerce platforms and business applications, such as inventory management, ERP, and shipping software. Generally, it supports over 60 eCommerce platforms, including Shopify, Magento, and WooCommerce. Also, API2Cart simplifies product catalog, order, and customer management, saving developers time by integrating various platform APIs into a unified solution.
Generally, it also includes 100+ API methods to work with store data such as products, orders, customers, shipments, categories, and more.
Here is the request structure of product.add method:
{
"name": "Bag",
"model": "bag_01",
"description": "Product description",
"price": 99.9,
"status": "disabled",
"categories_ids": "23,56",
"is_virtual": false,
"available_for_view": true,
"available_for_sale": true,
"old_price": 99.9,
"special_price": 56.9,
"cost_price": 65.9,
"quantity": 0,
"manage_stock": false,
"warehouse_id": "1",
"backorder_status": "true",
"weight": 0,
"weight_unit": "lb",
"barcode": "9770317847001",
"harmonized_system_code": "123456",
"country_of_origin": "123456",
"manufacturer": "Samsung",
"search_keywords": "key1,key2,key3",
"tags": "tag1,tag2",
"meta_title": "category,test",
"meta_description": "category,test",
"seo_url": "some seo url",
"taxable": true
}
Here is the response structure of product.list method:
{
"return_code": 0,
"return_message": "string",
"pagination": {
"previous": "string",
"next": "string",
"additional_fields": {},
"custom_fields": {}
},
"result": {
"products_count": 0,
"product": [
{
"id": "string",
"type": "string",
"u_model": "string",
"u_sku": "string",
"name": "string",
"description": "string",
"short_description": "string",
"price": 0,
"advanced_price": [
{
"id": "string",
"value": 0,
"avail": true,
"group_id": "string",
"quantity_from": 0,
"start_time": {
"value": "string",
"format": "string",
"additional_fields": {},
"custom_fields": {}
},
"expire_time": {
"value": "string",
"format": "string",
"additional_fields": {},
"custom_fields": {}
},
"additional_fields": {},
"custom_fields": {}
}
],
"cost_price": 0,
"quantity": 0,
"inventory": [
{
"warehouse_id": "string",
"quantity": 0,
"in_stock": true,
"priority": 0,
"additional_fields": {},
"custom_fields": {}
}
],
"group_items": [
{
"child_item_id": "string",
"product_id": "string",
"default_qty_in_pack": "string",
"is_qty_in_pack_fixed": true,
"price": 0,
"additional_fields": {},
"custom_fields": {}
}
],
"u_brand_id": "string",
"u_brand": "string",
"categories_ids": [
"string"
],
"stores_ids": [
"string"
],
"url": "string",
"seo_url": "string",
"meta_title": "string",
"meta_keywords": "string",
"meta_description": "string",
"avail_sale": true,
"avail_view": true,
"is_virtual": true,
"is_downloadable": true,
"weight": 0,
"weight_unit": "string",
"sort_order": 0,
"in_stock": true,
"on_sale": true,
"backorders": "string",
"manage_stock": "string",
"is_stock_managed": true,
"create_at": {
"value": "string",
"format": "string",
"additional_fields": {},
"custom_fields": {}
},
"modified_at": {
"value": "string",
"format": "string",
"additional_fields": {},
"custom_fields": {}
},
"tax_class_id": "string",
"special_price": {
"value": 0,
"avail": true,
"created_at": {
"value": "string",
"format": "string",
"additional_fields": {},
"custom_fields": {}
},
"modified_at": {
"value": "string",
"format": "string",
"additional_fields": {},
"custom_fields": {}
},
"expired_at": {
"value": "string",
"format": "string",
"additional_fields": {},
"custom_fields": {}
},
"additional_fields": {},
"custom_fields": {}
},
"tier_price": [
{
"qty": 0,
"price": 0,
"additional_fields": {},
"custom_fields": {}
}
],
"group_price": [
{
"id": "string",
"group_id": "string",
"price": 0,
"store_id": "string",
"quantity": 0,
"start_time": "string",
"expire_time": "string",
"additional_fields": {},
"custom_fields": {}
}
],
"images": [
{
"id": "string",
"http_path": "string",
"file_name": "string",
"mime-type": "string",
"size": 0,
"create_at": {
"value": "string",
"format": "string",
"additional_fields": {},
"custom_fields": {}
},
"modified_at": {
"value": "string",
"format": "string",
"additional_fields": {},
"custom_fields": {}
},
"alt": "string",
"avail": true,
"sort_order": 0,
"type": "string",
"additional_fields": {},
"custom_fields": {}
}
],
"product_options": [
{
"id": "string",
"product_option_id": "string",
"name": "string",
"description": "string",
"sort_order": 0,
"type": "string",
"required": true,
"available": true,
"used_in_combination": true,
"option_items": [
{
"id": "string",
"product_option_item_id": "string",
"name": "string",
"sort_order": 0,
"price": "string",
"weight": "string",
"quantity": 0,
"type_price": "string",
"sku": "string",
"is_default": true,
"additional_fields": {},
"custom_fields": {}
}
],
"additional_fields": {},
"custom_fields": {}
}
],
"u_upc": "string",
"u_mpn": "string",
"u_gtin": "string",
"u_isbn": "string",
"u_ean": "string",
"related_products_ids": [
"string"
],
"up_sell_products_ids": [
"string"
],
"cross_sell_products_ids": [
"string"
],
"dimensions_unit": "string",
"width": 0,
"height": 0,
"length": 0,
"discounts": [
{
"id": "string",
"name": "string",
"modifier_type": "string",
"value": 0,
"from_time": "string",
"to_time": "string",
"customer_group_ids": "string",
"sort_order": 0,
"additional_fields": {},
"custom_fields": {}
}
],
"additional_fields": {},
"custom_fields": {}
}
],
"additional_fields": {},
"custom_fields": {}
},
"additional_fields": {},
"custom_fields": {}
}
So, API2Cart follows RESTful architecture, offering ease of use for developers. Basically, it supports both JSON and XML data formats, catering to the needs of different programmers. API2Cart ensures secure communication with encryption and user authentication procedures. Additionally, this service offers comprehensive API documentation and technical support to help developers integrate and fine-tune their applications.
Conclusion
Thus, the REST is a simple yet powerful architecture that enhances web functionality. Generally, it is beneficial for developers looking to optimize their applications' API and integrate them seamlessly into the web. At API2Cart, we use REST API to ensure transparent data interaction. All methods are clearly documented to ensure ease of use.
Ready to turn REST knowledge into real integrations? Sign up for API2Cart and start connecting your software to 60+ eCommerce platforms through a single unified API. Reduce development time, simplify maintenance, and scale faster without building dozens of separate connectors. See how easy REST-based integrations can be in practice.
FAQs
- Stateless architecture - Each request contains all necessary information, eliminating the need for server-side session storage and improving scalability;
- Scalability and reliability - Statelessness and resource-based design allow RESTful systems to scale horizontally with minimal complexity;
- Uniform interface - Standard HTTP methods (GET, POST, PUT, DELETE) provide consistency across all interactions, simplifying development and maintenance;
- Use of web standards - REST relies on URLs, HTTP status codes, and widely supported data formats like JSON and XML;
- Language independence - Any programming language that supports HTTP can work with REST APIs;
- Lightweight data transfer - REST transmits only necessary data, reducing overhead compared to heavier protocols like SOAP;
- Widespread adoption - REST is broadly used across applications, ensuring strong ecosystem support and compatibility.
