> Text mode is super easy - you just set bytes in the correct memory location (0xb8000000 if I remember correctly). In addition you have to be using I/O ports

> Text mode is super easy - you just set bytes in the correct memory location (0xb8000000 if I remember correctly). In addition you have to be using I/O ports if you want to move the blinking cursor and other related stuff. > Writing an actual graphics driver is tricky - although there are some ways to get decent frame buffer modes (like VESA Bios Extentions), to do things really well requires thousands of lines of code before you can even get a pixel on the screen, and is different for every card. This is particularly painful because you have to switch back to real mode to be able to use VESA and other Bios interrupts. Thankfully it's not required if you're using a good bootloader like GRUB (which you should if you're doing an OS project, writing another bootloader is just more arcane hardware to work around). The multiboot specification allows you to ask for a video framebuffer from the bootloader, and you'll get a physical memory address where the linear video framebuffer resides. I bet UEFI has something similar too. So these days, with the help of your bootloader, doing graphics on a bare metal kernel is as easy as using the text mode.