Difference Between STL and Standard Library in C++

In C++, the term "Standard Library" and "Standard Template Library" are often misinterpreted as the same. Although they sound same with only a single word difference, they refer to the different part of the C++ programming language. In this article, we will learn what's the difference between the C++ Standard Library and Standard Template Library (STL).

C++ Standard Library

In C++, Standard Library is the set of classes and functions that enables operations for manipulating data structures, algorithms, input/output, and various utilities.

• This library contributes to the C++ ISO Standardization effort in order to provide a standardized, efficient, and versatile base for writing C++ programs.
• The evolution of the C++ Standard Library has paralleled that of the language; every revision of the standard of C++ saw new features added to it.
• The whole standard library of C++ is contained inside the 49 header files.
• The STL also is a part of standard library.
• The std namespace contains all the declaration of the components of the standard library.

For example, the cout, cin, printf(), scanf() are the part of the C++ standard library.

Standard Template Library (STL)

Standard Template Library (STL) is the subset of the C++ Standard Library and deals only with data structures and algorithms.

• It was developed by was designed by Alexander Stepanov and Meng Lee.
• STL have four major components: algorithms, containers, functions, and iterators.
• STL was made to be generic and reusable; due to this fact, a developer can create effective, type-safe, and flexible code.
• The STL insists on templates for polymorphism during compile time, which gives it high performance compared to traditional run-time polymorphism.
• Many ideas brought up and concepts introduced by the STL have been very influential in the rest of the C++ Standard Library.

For examples, vectors, set, maps, sort(), etc. are the part of STL.

Difference between STL and C++ Standard Library

Conclusion

The C++ Standard Library and the Standard Template Library (STL) are possibly the most important parts of the C++ programming environment, though having different logic of operation. The C++ Standard Library is rather all-encompassing: from easy language features to advanced data structures and algorithms, everything within it has been checked thoroughly by the ISO committee, showing uniform quality and uniform performance. The other by Alexander Stepanov called STL, focuses on the prescription for 'generic programming' and provides supporting algorithms, containers, iterators, and function objects that offer flexibility and efficiency via template-based abstraction.