Imperative Programming - What I learned for my test on Friday

Welcome to my profile! My name is Thiago, I'm a student of Computer Science and a trainee in IT Support in a private company. The idea of this post is to help me remember the content before taking the test I'll have on, you'll never guess: this Friday! I also hope that it helps other people interested in the subject.

Concept

Imperative Programming is the first programming paradigm that is studied in college, even if it's never mentioned by this term. You'll recognize it by the programming languages that are created from it —¹ C, Perl, JavaScript, etc — due to their simplicity and "direct" way of writing instructions: copying the imperative mood in natural languages ("do this", or "do that in this order"), telling the computer what (and how) to do, step by step, using variables, and altering the state of the process while executing.

See below the details for each of the mentioned characteristics.

Exempli gratia

Most of what I described above becomes clearer when using an example in C.

int a = 0, b = 5, i;      //Define 'a' as 0, 'b' as   5, and 'i' stays uninitialized

for(i = 0; i < b; i++){   //Define 'i' as 0, and while its value is lower than the value of 'b', execute the block of code below and add 1 to 'i' value
    if(i == 2){           //If 'i' equals 2, execute the block of code below
        printf("%d", i);  // Print in the terminal the value of 'i'
    }
    else a++;             //If the value isn't equal to 2, add 1 to 'a' value
}

See how the whole code block, based on the comments of each line, is really inspired by the imperative mood? Beyond that, observe how the order of commands is really specific.

Furthermore, both the for loop and else statement lines are examples of altering the state of the process while executing it — the value of 'i' and 'a' changes constantly in the memory, so the computer never repeats its processes in the same way as before.

References

Sebesta, R. W. (2018). Concepts of programming languages (12th ed.). Pearson.
Imperative programming. (2026, August 15). In Wikipedia. https://en.wikipedia.org/wiki/Imperative_programming