# Exercise 1 - Variable Declaration

## 1 Question

What is a variable?

### 1.1

A variable is a place to store a piece of information. Just as you might store a friend's phone number in your own memory, you can store this information in a computer's memory. Variables are your way of accessing your computer's memory.

## 2 Question

Which are the two kinds of variables and what is the difference between them?

### 2.1

There are two different kinds of variables, discrete-time and continuous-time variables. Discrete-time variables change value only at event instants, whereas continuous-time variables may change value both between and at events.

## 3 Question

What is a parameter?

### 3.1

A parameter is a special kind of constant, which is implemented as a static variable that is initialized once and never changes its value during a specific execution.

## 4 Declaring Variables

Define a class Matrices that declares the variables m1, m2, m3, m4 all being matrices with Integers respectively Real numbers. Make at least one of them an array. Let m1 and m2 be parameters, m3 a regular variable and m4 a constant.