All language subtitles for 6_Recipe for Computing

Remember that in the 1950s,

computer scientists used punch
cards to store programs.

These punch cards represented

bits that the CPU would read and

then perform a series of

instructions based on
what the program was.

The binary code could
have looked like this,

and the instructions will
be translated to this,

grab some input data from
this location in memory.

Using the input
data, do some math,

then put some output data
into this location in memory.

But storing programs
on punch cards

was a long and tedious task.

The programs had to be kept on

stacks and stacks
of punch cards.

Computer scientists needed
a better way to send

instructions to a
machine, but how?

Eventually a language was

invented called
assembly language,

that allowed computer
scientists to use

human readable
instructions assembled

into code that the
machines could understand.

Instead of generating
binary code,

computer scientists
could program using

machine instructions like this.

Take integer from register 1,

take integer from register 2,

add integer from
register 1 and register

2 and output to register 4.

This example makes it look
like a human could read it,

but don't be fooled.

Let's take an example of
saying something simple like,

hello world in
assembly language.

It looks pretty robotic,

don't get me wrong that's still

an improvement over its
binary code cousin.

But assembly language was

still a thin veil
from machine code.

It's still didn't let
computer programmers use

real human words to
build a program,

and a program that was written
for a specific CPU could

only be run on that
CPU or family of CPUs.

A program was needed that could

run on many types of CPUs,

enter compiled
programming languages.

A compiled programming
language uses

human readable instructions and

sends them through a compiler.

The compiler takes the
human instructions

and compiles them into
machine instructions.

Admiral Grace Hopper invented

this to help make
programming easier.

Compilers are a key
component to programming and

helped pave the road that led us

to today's modern computing.

Thanks to compilers, we can
now use something like this,

and it would be the
same thing as this.

Computer scientists
have developed

hundreds of programming
languages in

the past couple of decades
to try and abstract

the different CPU instructions
into simpler commands.

Along the way, another
type of language emerged

that was interpreted
rather than compiled,

interpreted languages aren't
compiled ahead-of-time.

A file that has code
written in one of

these languages is
usually called a script.

The script is run by

an interpreter which
interprets the code

into CPU instructions
just in time to run them.

You'll learn how to write code

using a scripting
language later in

this program as an IT
support specialist,

scripting can help you by
harnessing the power of

a computer to perform
tasks on your behalf,

allowing you to solve a problem

once and then move on
to the next thing.

Programming languages are
used to create programs

that can be run to perform
a task or many tasks.