A program is a set if instructions written by a human for a computer to perform. These instructions don’t completely mimic the real way humans communicate, so as a program gets more and more complex, it becomes harder even for its own writer to understand, so special measures to keep it readable must be taken during the writing.
Programming languages are artificial languages that strive to make it easier for a human to write code for a computer by reaching a middle point between it being actionable by a computer and relatively easy to read by a human. Java and Javascript are two of such languages. It is important to note they have no relationship whatsoever, other than the was created during the popularity peak of the other.
A synonym for Javascript is ECMAScript, which also means the standard that defines what should be considered Javascript.