Computer Science Terms

Any time you learn a new subject, computer science included, you’ll find new terms. To help out we’re building this glossary of computer science terms.

This particular list is geared mainly towards Java programming, although many of the terms are relevant whatever language you’re learning.


Symbol used to check if two values are not equivalent.
1 != 2
Logical and. Used to combine two boolean conditions where both conditions must be true for the combined statement to be true.
true && true == true
true && false == false
false && true == false
false && false == false
Two equals signs are used to test equality.
int x = 2;
int y = 3;
if (x == y)
   System.out.println("They're equal!");
Logical or. Used to combine two boolean conditionals where the combined statement is true if either side of the or is true.
true || true == true
true || false == true
false || true == true
false || false == false


abstract class
A class that cannot be instantiated and may contain abstract methods
abstract method
A method with a name, parameter types and return type; but without implementation. Typically used within an abstract class when the implementation is not known for a specific method.
Exception thrown when an impossible math condition is used. Most common example is when you try to divide by zero.


A group of statements. In Java, and many other languages,  blocks are surrounded by { and } symbols.
Primitive data type with only two possible values, true or false.


An event that disrupts the normal flow of a program


Exception thrown when trying to access a property or method of a null object.