[SPCA] Add note on endianness

semester3/spca/parts/00_asm/00_intro.tex

@@ -4,6 +4,9 @@ Notable examples are \texttt{x86}, \texttt{RISC-V} (this one is open-source!), M
 
 \texttt{x86}-Assembly files usually use the file extension \texttt{.s} or \texttt{.asm}
 
+Most CPU architectures (including \texttt{x86}, most \texttt{ARM} and base \texttt{RISC-V} implementations) are little endian (also sometimes called right-to-left or right-aligned)
+and thus have the LSB on at the lowest address.
+
 \fancydef{Microarchitecture} The implementation of the ISA. It defines the actual hardware layout and how the individual instructions are actually implemented
 and thus also defines things such as core frequency, cache layout and more.