C++ is a very comprehensive, vast, and powerful language is perhaps the most concise definition (and over simplification) of C++. Although considered a high level language, with the advent of languages like Python, and Ruby, it is now considered low level along the lines of C, and rightfully so. The language contains many constructs (most prominently - pointers) which it borrows from C, a low level programming language, and is highly used in areas like Compiler Design, Video Game Development, and IoT. It is a fully compiled language, meaning, it compiles the code to native binary which can be directly executed on the system. However, since it is compiled to native code, the binary compiled on one architecture and/or kernel cannot be used on different architecture/kernel without recompilation. Hence, if one compiles a C++ program on Linux, the same binary cannot be used on, say, Mac OS.
The reason for its prominance in fields like IoT is that it has quite low memory footprint, that is, it used a very low amount of system memory to work, depending on the program or software written. This is, again, due to the fact that the language compiles code to native binary and the generated binary does not rely on a virtual machine for code execution on the system.
Now, with all the power and amazing features of C++, one must still understand where the language is most suitable and where not, because, in the wrong situation, C++ can wreak havoc on one's system or simply be too cumbersome to use. Let's take a glimpse into this.