Python Day 1 – Why Python, and What Even Is It?

So I started a Python course, and I'm going to write down what I learn each day here. Mostly for me, but maybe it helps someone else too.

What is Python?

Python is a general purpose, high level programming language. "High level" just means it's easy for humans to read. Compare this:

no1 = 10
no2 = 20
print(no1 + no2)

with assembly, which is much closer to what the machine understands:

MOV AL, 10
MOV BL, 15
ADD AL, BL

Yeah. I'll take Python.

Where is Python used?

Pretty much everywhere:

• Data Science, ML, AI (handles huge data well)
• Web apps (Django, Flask)
• Desktop apps, scripting, automation
• Games, IoT, network programming

A bit of history

• Python came out in 1991 (Java in 1995)
• Python 2 in 2000, Python 3 in December 2008
• Python 3 isn't fully backward compatible with Python 2, which is why everyone just uses Python 3 now

Compiled vs Interpreted

• Compilation = translate the whole program at once
• Interpretation = translate line by line

Python is an interpreted language. There are also different implementations: CPython (the normal one, written in C), Jython (Java), IronPython (.NET), PyPy.

Pros and cons we discussed

Good: simple, open source, interpreted, extensible, high level, platform independent, dynamically typed.

Not so good: slower than C/C++/Java, uses more memory, type errors show up only at runtime, and it's not really used for mobile apps.

Small fun thing to try:

import sys
print(sys.copyright)

That's Day 1.