The document discusses the most popular programming languages for 2021, highlighting trends based on various metrics such as job postings and developer surveys. Key languages include Python, Java, and JavaScript, with additional insights on their use cases and related technologies. It also addresses the reliability of rankings and the essential skills software engineers should possess.

1. https://softuni.org
The Most Wanted Programming Languages for 2021:
JavaScript, Java, Python, C#, C++, PHP and Others
Programming Languages: Trends for 2021
Svetlin Nakov, PhD
Co-Founder, Innovation and
Inspiration Manager at SoftUni
https://nakov.com

2.  The Most Used Programming Languages in 2020:
 Python, Java, JavaScript, C#, C++, PHP
 Programming Languages Rankings:
 LinkedIn Jobs, GitHub, Stack Overflow, Google
Trends, PYPL, IEEE, TIOBE, Jobs.bg
 The Skills of the Software Engineers: Coding,
Algorithms, Development Concepts, Technologies
 Programming Languages: Trends for 2021
Table of Contents

3. The Most Used Programming
Languages in 2020

4.  Python
 Best for: data science, machine learning, AI, Web development
 Comes with: data science toolkits, Jupiter, NumPy, TensorFlow, PyTorch, Django /
Flask, MySQL / PostgreSQL, HTML + CSS + JS front-end
 Java
 Best for: enterprise applications, back-end apps, Web apps, Android apps
 Comes with: Spring Framework, Spring MVC, Java EE, Hibernate, MySQL
/PostgreSQL + front-end technologies (HTML, CSS, JS front-end, React)
 JavaScript
 Best for: modern front-end apps, cross-platform UI, back-end apps
 Comes with: HTML + CSS + front-end technologies (HTML5, React, Angular, VueJS),
JS back-end technologies (Node.js, Express, MongoDB), TypeScript
Mainstream Languages and Frameworks
4

5.  C# / .NET
 Best for: back-end apps, Web apps, enterprise applications, desktop apps
 Comes with: .NET Core, ASP.NET MVC, Entity Framework, SQL Server, front-end
technologies (HTML, CSS, JS front-end, React)
 C++
 Best for: embedded / IoT development, graphics and game development, finance,
system programming, high-performance back-end computing
 Comes with: C++, STL, Boost, CMake, Qt, POCO C++, Unreal Engine
 PHP
 Best for: server-side Web apps, dynamic Web sites, e-commerce projects
 Comes with: MySQL, PHP frameworks (Laravel, Symfony, CodeIgniter), front-end
technologies (HTML, CSS, JS front-end, React), WordPress
Mainstream Languages and Frameworks (2)
5

6.  TypeScript – strongly-typed JavaScript, less prone to errors, good
for big and complex projects, used in Angular and Next.js
 Swift – modern general-purpose language, mostly used on the
Apple's ecosystem (iOS, macOS, alternative to Objective C)
 Kotlin – simplified syntax for the Java and Android ecosystem
 Scala – rich functional programming for the Java ecosystem
 Ruby – dynamic language, build for simplicity and productivity
(mostly for back-end Web apps, alternative to PHP and Python)
 Visual Basic – scripting for Windows (slowly disappearing)
Less Popular Languages and Frameworks
6

7.  Go – modern highly-efficient server-side development language
(alternative to C++)
 Rust – multi-paradigm back-end language designed for
performance and safety (alternative to C++)
 C – language for system programming and low-level
development
 R – specialized language for statistics and data analytics
 Dart – front-end language for building UI with Flutter
 Perl – old-fashioned powerful back-end language
Specialized Languages
7

8. 8
 Many technologies are related to programming, but are not
programming languages
 SQL
 Database query and manipulation language
 HTML and CSS
 Visualize Web content (text + images + links)
 XML and JSON
 Store and transport data
Non-Programming Languages

9. The Most Popular Languages in 2020
Programming Languages Rankings

10. 10
 LinkedIn Jobs (Dec 2020):
 Java ⟶ 356 482 results
 Python ⟶ 316 388 results
 JavaScript ⟶ 312 553 results
 C++ ⟶ 171 671 results
 C# ⟶ 131 249 results
 PHP ⟶ 93 587 results
 Note: open jobs != total jobs
LinkedIn Jobs Rankings by Language

11. 11
 Top languages in GitHub
(Octoverse 2020 report):
 #1: JavaScript
 #2: Python
 #3: Java
 #4: TypeScript
 #5: C#
 #6: PHP
 Note: only public open-source projects from GitHub are included!
GitHub Ranking by Language

12. 12
 PYPL PopularitY of Programming Language (how often language
tutorials are searched on Google)
 PYPL ranking (Dec 2020)
 #1: Python
 #2: Java
 #3: JavaScript
 #4: C#
 #5: C++
 #6: PHP
PYPL: Programming Languages by Google Trends

13. 13
 Stack overflow – total number of questions by tag:
 E.g. https://stackoverflow.com/questions/tagged/java
 Stack Overflow all time questions asked
 JavaScript ⟶ 2 138 968 questions
 Java ⟶ 1 740 471 questions
 Python ⟶ 1 609 659 questions
 C# ⟶ 1 453 717 questions
 PHP ⟶ 1 384 176 questions
 C++ ⟶ 705 273 questions
Stack Overflow: Questions Tagged by Lang

14. 14
 Stack overflow developer survey 2020:
 https://insights.stackoverflow.com/survey/2020
 Stack Overflow dev survey 2020
 #1: JavaScript
 #2: Python
 #3: Java
 #4: C#
 #5: PHP
 #6: TypeScript
Stack Overflow Developer Survey

15. 15
 IEEE top languages for 2020:
 Combine 11 metrics: Google, GitHub,
Stack Overflow, Twitter, Reddit, others
 IEEE top langs for science and education:
 #1: Python
 #2: Java
 #3: C
 #4: C++
 #5: JavaScript
 #6: R
IEEE Programming Language Rankings

16. 16
 TIOBE Index: programming languages on the most popular search
engines (not only Google)
 TIOBE Index (Dec 2020):
 #1: C
 #2: Java
 #3: Python
 #4: C++
 #5: C#
 #6: Visual Basic
TIOBE: Languages on Search Engines

17. 17
 Jobs.bg ranking by programming
languages for Bulgaria (Dec 2020):
 Java ⟶ 1049
 JavaScript ⟶ 635
 Python ⟶ 432
 C# ⟶ 299
 PHP ⟶ 283
 C++ ⟶ 169
Ranking for Bulgaria: Jobs.bg, LinkedIn BG

18. 18
 Why the rankings for the programming language
popularity are not much reliable?
 Based on "by keyword search"
 "JavaScript" can match also "Java" and "PHP" jobs
 Based on what people search, not what they use
 Research methodology is quite important
 Think what do you want to measure!
Why Rankings Are Not Reliable?

19. The Skills of the
Software Engineers

20.  4 main groups of skills:
 Coding skills – 20%
 Algorithmic thinking – 30%
 Fundamental software
development concepts – 25%
 Programming languages and
software technologies – 25%
Skills of the Software Engineers
20
Language-
independent skill
Language-
independent skill
Language-
independent skill
Language-
dependent!

21. Programming Languages:
Trends for 2021

22. 22
 Top 5 mainstream programming languages for 2021:
 Python
 JavaScript
 Java
 C#
 C++
 The others are less significant
What to Expect in 2021?
 Non-mainstream languages for 2021:
 Rust, Go (high-performance)
 Dart (Flutter framework)
 R (for statistics)

23. SoftUni – https://softuni.org 2