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+# Bytecode
+Bytecode, also known as *p-code* (for *portable code*) is a machine language-like representation
+of a program. Unlike actual machine code, it has a higher-abstraction level, since commonly
+bytecode is bespoke to the [language](programming_language.md) that it's meant to be used with, supporting high-level
+operations such as closures, memory management, dynamic typing, etc..
+
+Usually bytecode is meant to be run in a [virtual machine](virtual_machine.md); this is common for scripting
+languages in order to achieve an usable performance, bytecode being a compact representation
+is more cache friendly than an [AST](abstract_syntax_tree.md) so it allows for faster execution.
+
+In other cases, bytecode is used as an intermediate representation for compiled languages,
+before lowering down to more machine-specific code.
+
+## Examples
+### PL/0 p-code
+- `lit` (load constant)
+- `opr` (operation, this opcode packs multiple arithmetic ops.)
+- `lod` (load variable)
+- `sto` (store variable)
+- `cal` (call procedure)
+- `int` (increment register)
+- `jmp` (unconditional jump)
+- `jpc` (conditional jump)
+
+TODO more info
+
+### Lua bytecode
+TODO