People often ask this question . What i the purpose of C++ and why it is still in the market of developers. Let's see what it has

1. Programming in CPlusPlus
Before learning about programming in C++ , let me mention some points that show why you
have chosen to program in C++ rather than C# or Vb.Net.
Where C++ is used?
Giants like Amazon.com, eBay, and Google often use C++. Google uses C++ for performance
critical applications.
Facebook compiled PHP with C++ compiler. A large amount of Windows portion has been
developed in C++
Most commercial Java Runtime Environments (JRE) are written in C++.
C++ lets you work with unmanaged code, which most of the code in the world still is. Native
C++ is closer to the metal than C# or other CLI languages that run atop the .Net platform, and in
many applications that’s important.
C++ dominance in Drivers and Game development
As far as drivers programming is concerned, C++ is the language that everyone is looking for.
The old assembly language can also be used for driver development but C++ organizes the code
in such a beautiful way that it provides some room for the programmer to implement further
extending the code in future.
C# or Java have a JIT support that cannot be as fast as C++ code. However C++ code used to be
significantly faster for a long time, and also today still is in many cases. This is mainly due to the
more advanced JIT optimizations being complicated to implement, and the really cool ones are
only arriving just now.
With C++ , the programs are are very faster as compared to C# or Java JIT
“Most game engines are written in C++”
“Games: Doom III engine. Sierra On-line: Birthright, Hellfire, Football Pro, Bullrider I & II,
Trophy Bear, Kings Quest, Antara, Hoyle Card games suite, SWAT, and too many others to
list… Blizzard: StarCraft, StarCraft: Brood War, Diablo I, Diablo II: Lord of Destruction,
Warcraft III, World of Warcraft. Quicksilver: Shanghai Second Dynasty, Shanghai Mah Jongg
Essentials, Starfleet Command, Invictus, PBS’s Heritage: Civilization and the Jews, Master of
Orion III, CS-XII. Microsoft: all games. EA: video game engine. Byond: a “world” development
platform..”
I’m certain there are many others as well. An infamous game called Trespasser, a dinosaur game,
was written in c++ as well, I base this simply on knowing the game executable well and the
game’s functions are definitely c++.
reference to the above paragraph
https://answers.yahoo.com/question/index?qid=20070513141231AAKEK10

2. What the experts say about C++?
1. C++ is a high-level language that lets you get close to the hardware.
When programming games it is necessary to write highly optimized code in order to get the best
performance from the platform. We do this by employing a variety of programming
methodologies and memory and bit manipulations. We generally do not make use of managed
libraries that abstract away such functionality. Development environments for the language also
support assembly code blocks to allow the programmer to get even closer to the hardware.
2. C++ is compiled for the specific platform.
C++ has a variety of compilers that create binaries specific to the platform directly without the
need to first be compiled into an intermediate language then some form of virtual machine
thereafter which significantly slows down code.
3. C++ supports legacy and resource-constrained hardware very well.
C and C++ have been around for years and are very well standardized according to the official
specification. Although compilers change in their specification, the C++ language itself carries
over useful and established techniques for efficient coding in whatever has gone before and
arguably what the future has to offer.
4. C++ can be used to write a variety of code.
Because of C++’s extreme flexibility, you will find that code used to run on a specific platform
will in itself be running in conjunction with binaries coded in the same language, so the
programmer can in theory use the language to write anything for the platform.
Those are just some of the ‘in-a-nutshell’ reasons why C++ is used over other languages for
game dev.
reference: http://www.dreamincode.net/forums/topic/236764-why-are-game-engines-written-in-
c/
So, for core System Programmers, C++ is the best option