Computing interpreters are quite similar to computer compilers, in that they provide computer programmers with a way to use extremely human readable programming languages. As the world of computers have evolved, so has the world of computer programming languages. As a result, the distinction between computing interpreters and computer compilers has blurred considerably.
In their most basic sense, computing interpreters take a series of human readable instructions, then convert them into something the computer will understand, just like computer compilers. Different computing interpreters accomplish this feat in different ways, though.
Some computing interpreters will run through the source code provided to them by the programmer one by one. What this means is that, rather than translating the entire source code into a language the computer will understand, the computing interpreter will run through each line, converting it into computer code one by one as it runs through the file. These types of computing interpreters are clearly distinct from the concept of computer compilers, which create a program the computer can run directly.
Other computing interpreters might run through the human source code and create a series of more efficient instructions before running the program. This can help to improve the speed of the program. Both this type of computing interpreter and the former type can be clearly distinguished from computer compilers: they both require the computing interpreter in order to run the program.
But with the development of the Java programming language and virtual machine, the lines blur a bit. The Java programming language is compiled into instructions that run directly on the Java virtual machine. The Java virtual machine is simply a virtual computer. Due to the widespread use of Java, it is almost as if programs made in Java were really made by a compiler.
Luckily, the difference between computing interpreters and computer compilers is little more than a battle of semantics. At their core, computing interpreters and computer compilers both work to provide us with a world of software possibilities.