Clip Studio Paint - A great program and a great alternative to Photoshop! I've been using CSP since 2018 and I'm still very glad I made the switch over from SAI. The desktop version of Clip is a one time purchase only (tablet and mobile has a ~5 USD/month subscription) and it comes with tons of features. The EX version even has helpful tools for comics and even tools for animation! The price for Clip is very affordable (much better compared to Photoshop's asinine prices) and it even goes on sale for 50% off occasionally throughout the year!
Paint Tool SAI/2 - A great starter program for those looking to get into digital art! Goes for about 50 USD.
Procreate - I love this little app for the iPad! One of the reasons I got my iPad was purely because I wanted to try out Procreate. If you're coming from a program like SAI or Clip, you'll have to get used to the gesture controls and the simple interface, but there's so much you can do with a simple app like Procreate.
These programs below I haven't tried myself, but they're all free and used by many digital artists who can't afford the options above!
Fire Alpaca - I've used this program once when it was making the rounds when it came out, but another great starter program for those who want to try out digital art. It's free as well!
Notepad++ - Used this for coding my site!
W3Schools, I used this for help coding my site!
GIFcities, An archive of old Geocities GIFs and graphics!
Zonelets, a blogging engine for Neocities!
Prospect App: a program for Macs that lets you view Procreate images!
Daylio, another mood tracking app and sections if you wanna get into journaling!
Obsidian, a note taking program/app! As of writing I recently switched to this app to organize my head when it came to worldbuilding. So far, I love it!