Python version in downloads

[Programit]

This is a dumb question from a Python newbie.
I have experience with other languages but never touched python beyond a few online tests.
Whats the story with the Python versions.
I know that version 2.X is different from 3 in many ways, and I have downloaded both 3.6.4 and 2.7.14, but what about similar versions.
I thought I'd finally try Python and setup my linux and Windows machines for development and noticed that in the download section the version numbers seem odd. Top to bottom they go 3.4.8, 3.5.5, 3.6.4, 3.6.3, 3.3.7, 2.7.14, 3.4.7 etc....
3.4.8 was released 2 months after 3.6.4 with 3.5.7 released on the same day as 3.4.8?!
I assume that you can't upgrade direct from 3.3.7 to 3.6.3?
If I create a project with 3.6.4 do I have to stay with 3.6 branch which would seem very restrictive.
If not then why release a newer version with lower number.

[stranac]

The lower version numbers, such as 3.4.8 are bugfixes.
They don't add any of the features 3.6 has, just fix existing bugs in 3.4.x

Just install the latest 3.x (the highest version number), and you'll be able to run all code written for older 3.x versions (except for some minor things, which you can very rarely run into, like added keywords)

[Programit]

I assume its primarily for compatibility, or is there other reasons why not just update 3.4 to 3.6 or similar.
Thanks for the quick reply.
Just starting to fiddle with a couple of IDEs and getting my head around the basics.

[stranac]

Some people are just stuck on old versions of python, for whatever reason.
You shouldn't concern yourself with this, and should use the latest version available.

[metulburr]

They are
Major.Minor.Bugfix
So for version 3.6.4
3 is the major version, 6 is the minor version, and 4 is the bugfix.

So hence there could be numerous bug fix releases for different minor versions. And until 2.x dies in 2020 there could be for them as well. If you really want to know the nitty gritty details of each version check the release notes under the version list https://www.python.org/downloads/

noticed that in the download section the version numbers seem odd. Top to bottom they go 3.4.8, 3.5.5, 3.6.4, 3.6.3, 3.3.7, 2.7.14, 3.4.7 etc....

This just means they had a bugfix for 3.4 and 3.5 they uploaded after the current latest version (3.6.4). If you look in the release notes these fixes are actually old news and were already fixed in the 3.6.4 update over 2 months ago. So hence the latest release date doesnt mean anything in terms of "latest". The actual version number matters.

The latest (highest number) will always be at the button on top for 3.x and 2.x. The 3.x one is the one you should download unless you know you need another version for whatever reason.

is there other reasons why not just update 3.4 to 3.6 or similar.

Most of the time its just being lazy. They have stuff setup the way they want, and there is no need to update until something forces them to such as reinstalling the operating system for example.

[Programit]

Thanks for the responses. Clarified my initial thoughts.
Cheers.