# Grok all the things

grok (v): to understand (something) intuitively.

# Fortran

๐ถ ย Children (ELI5)

Hey there, coding explorers! Today, we're going to embark on an amazing adventure into the world of Fortran, a classic programming language that has played a significant role in the history of computing. Get ready to learn about its origins, its unique features, and examples of how it has been used! Are you excited? I sure am! Let's dive in!

## ๐ A Brief History of Fortran

Once upon a time in a land filled with punch cards and gigantic computers, there was a groundbreaking programming language named Fortran. Created way back in the 1950s by IBM's John Backus and his team, Fortran (short for FORmula TRANslation) was the first high-level programming language ever!

At that time, people programmed computers using low-level assembly languagesโthis was really time-consuming and difficult to understand. But Fortran changed all that! It allowed scientists and engineers to write code in a more human-friendly way and let the computer handle the hard work of converting it into machine code. How cool is that?

## ๐จ The Artful Syntax of Fortran

Fortran looks quite different from the programming languages you might be more familiar with, like Python or JavaScript. It has its own unique style! Let's check out some examples.

### โ๏ธ Variables and Types

In Fortran, you can store numbers, words, or even a combination of multiple values! Here are some basic data types:

• INTEGER: Whole numbers like 1, 2, or 3.
• REAL: Decimal numbers like 3.14.
• CHARACTER: A single character (like 'A' or 'B') or a string (like 'hello').
``````INTEGER :: count
REAL :: pi
CHARACTER(LEN=10) :: greeting
``````

### ๐ Loops

Loops are a fantastic way to repeat something over and over again. In Fortran, you can use the `DO` loop to achieve this!

``````INTEGER :: i
DO i = 1, 10
PRINT *, 'Iteration:', i
END DO
``````

### ๐ง Conditionals

Sometimes, you want your program to make decisions based on specific conditions. Fortran's `IF` statement comes to the rescue!

``````INTEGER :: temperature
temperature = 25

IF (temperature > 20) THEN
PRINT *, 'It is warm outside.'
ELSE
PRINT *, 'It is cold outside.'
END IF
``````

## ๐ Famous Applications of Fortran

Fortran has been used in countless incredible projects. Here are a few examples that might just blow your mind!

1. Space Exploration : Fortran was used by NASA during the Apollo missions to model the trajectories of spacecrafts heading to the moon!

2. Weather Forecasting : Fortran has been the backbone of many weather prediction models, allowing meteorologists to warn us about hurricanes, tornadoes, and other extreme weather events!

3. Physics Simulations : Fortran has played a huge role in high-performance computing for scientific research, especially in the fields of particle physics and nuclear engineering. It helps simulate complex scenarios and predictions. How powerful!

## ๐ฉโ๐ป Let's Write Some Fortran Code

Now that you know what Fortran looks like and what it can do, let's write our very own Fortran program together! We will create a simple program that calculates the area of a rectangle. Are you ready? Let's code!

``````PROGRAM AreaOfRectangle
IMPLICIT NONE
INTEGER :: length, width, area

PRINT *, 'Enter the length of the rectangle:'

PRINT *, 'Enter the width of the rectangle:'

area = length * width

PRINT *, 'The area of the rectangle is:', area
END PROGRAM AreaOfRectangle
``````

Whoa! We did it! Notice how we used `PRINT` to display messages and `READ` to get input from the user. Our program then calculated the area and displayed it on the screen. Great job!

## ๐ Embracing the Legacy

Although Fortran may seem old and unfamiliar, it has a rich history and a strong presence in many important fields of science and engineering. Plus, learning about Fortran helps us appreciate how far we've come in the world of programming languages.

Exploring Fortran has been a marvelous adventure, hasn't it? Remember, there's always more to learn and discover, so keep your curiosity alive, my fellow coding explorers! Happy coding!

Grok.foo is a collection of articles on a variety of technology and programming articles assembled by James Padolsey. Enjoy! And please share! And if you feel like you can donate here so I can create more free content for you.