Detail interrupt vector table in 1-the-basics.mdx

src/content/chapters/1-the-basics.mdx

@@ -90,7 +90,7 @@ If you've ever written code that interacts with the OS, you'll probably recogniz
 
 User space to kernel space control transfers are accomplished using a processor feature called [*software interrupts*](https://en.wikipedia.org/wiki/Interrupt#Software_interrupts):
 
-1. During the boot process, the operating system stores a table called an [*interrupt vector table*](https://en.wikipedia.org/wiki/Interrupt_vector_table) (IVT; x86-64 calls this the [interrupt descriptor table](https://en.wikipedia.org/wiki/Interrupt_descriptor_table)) in RAM and registers it with the CPU. The IVT maps interrupt numbers to handler code pointers.
+1. During the boot process, the operating system stores a table called an [*interrupt vector table*](https://en.wikipedia.org/wiki/Interrupt_vector_table) (IVT; x86-64 calls this the [interrupt descriptor table](https://en.wikipedia.org/wiki/Interrupt_descriptor_table)) in RAM and registers it with the CPU. The IVT maps interrupt numbers (signifying the type of interrupt) to the memory address of the code (almost always system code, not user space code) handling the interrupt. For example, to read keyboard input, the user space program can make a system call that issues an interrupt, which will cause the kernel to look up the interrupt in the IVT and start running the interrupt handler.
 
   <img src='/images/interrupt-vector-table.png' loading='lazy' style='max-width: 300px; margin: 0 auto;' alt='A image of a table captioned "Interrupt Vector Table". The first column, labeled with a number sign, has a series of numbers starting at 01 and going to 04. The corresponding second column of the table, labeled "Handler Address", contains a random 8-byte-long hex number per entry. The bottom of the table has the text "So on and such forth..."' width='555' height='463' />