Active Template Library (ATL)

The Active Template Library (ATL) is a C++ template-based library developed by Microsoft, primarily designed for creating small, fast Component Object Model (COM) objects, such as ActiveX controls and OLE DB providers, with minimal overhead. It provides a lightweight framework that abstracts the…

Key facts

First appeared: 1996
Category: technology
Problem solved: ATL was created to simplify the development of COM components, particularly ActiveX controls, while ensuring they remained lightweight and efficient. Before ATL, developers either used the verbose and complex raw COM SDK or the heavier Microsoft Foundation Classes (MFC), which added significant overhead unsuitable for internet-downloadable components.
Platforms: Microsoft Windows

Related technologies

MFC (Microsoft Foundation Classes)
Win32 API
OLE DB
Visual C++
COM (Component Object Model)
ActiveX

Notable users

Financial institutions (for high-performance COM-based systems)
Microsoft (internal Windows component development)
Enterprise software vendors (for legacy Windows applications)