Can you explain what declaring a variable with the keyword var means in programming languages?

In programming languages such as Dart (used in Flutter), the keyword var is used to declare a variable with an implicit type. This means that the compiler infers the variable's type based on the assigned value during initialization.

For example:

var name = "Ivan"; // The compiler understands that name is a String
var age = 25;       // The compiler understands that age is an int

After initialization, the variable's type is fixed and cannot change. Using var is convenient when the type is obvious from the context, and it allows writing shorter and cleaner code.