One of my earliest memories is drawing a stickman party in
MS Paint on my dad's laptop. The WinXP version. So that's my first ever art program I guess!
He also had
Photoshop installed, so a little later I started drawing in it too. For a while I used both paint and photoshop interchangeably, usually making the lineart and flat colors in paint and then adding shading or glowing effects in photoshop
You can see a little bit of shading on its head and paw here. This is the only picture from that time that I've found but there are more somewhere on the web I'm sure.
I also drew a lot of stuff on a website called
Toonator. It had its own flash-based drawing space. Unfortunately the site is gone now and all of my old art and animations are gone with it as well.
Here's one screenshot I found
Then in 2014-2015 I downloaded a trial version of
Paint tool SAI on my tiny netbook and it's been my program of choice since then.
Well, I use SAI2 right now to be more specific.
I tried using other programs but SAI is what I'm most comfortable with. It's simple and fast, and I like its brush engine - I'd rather make brushes myself rather than install them from online. I also use Krita when I need to draw something for uni since it has an android version, but I personally don't like how drawing in it feels, so I don't use it for personal art. It's SAI2 on my laptop and Ibis Paint on my tablet forever or untill I get sick of them