Why is “null” present in C# and Java?

Question

We noticed that lots of bugs in our software developed in C# (or Java) cause a NullReferenceException.

Is there a reason why \"null\" has even been included in the l

Answer 1

Null in C# is mostly a carry-over from C++, which had pointers that didn't point to anything in memory (or rather, adress 0x00). In this interview, Anders Hejlsberg says that he would've like to have added non-nullable reference types in C#.

Null also has a legitimate place in a type system, however, as something akin to the bottom type (where object is the top type). In lisp, the bottom type is NIL and in Scala it is Nothing.

It would've been possible to design C# without any nulls but then you'd have to come up with an acceptable solution for the usages that people usually have for null, such as unitialized-value, not-found, default-value, undefined-value, and None. There would've probably been less adoption amongst C++ and Java programmers if they did succeed in that anyhow. At least until they saw that C# programs never had any null pointer exceptions.