Lisp

1. Symbolic Expression: Programs and data are represented as lists of symbolic expressions.
2. Functional Programming: Treats computation as the evaluation of mathematical functions.
3. Dynamic Typing: Variable types are determined at runtime.
4. Code as Data: Code and data are interchangeable, enabling powerful metaprogramming.

Before learning Lisp, it's beneficial to have:

1. Understanding of Programming Concepts: Familiarity with basic programming concepts like variables, data types, control structures, and functions.

2. Problem-Solving Skills: Ability to break down problems into smaller, manageable tasks and devise solutions.

3. Logic and Mathematics: Understanding of logic and mathematical concepts, as Lisp often deals with symbolic computation and functional programming paradigms.

4. Familiarity with Functional Programming: Exposure to functional programming concepts can be helpful, as Lisp is a functional programming language.

By learning Lisp, you gain:

1. Strong Foundation in Functional Programming: Lisp introduces you to functional programming concepts, which are valuable in many programming paradigms.

2. Metaprogramming Skills: You'll learn how to manipulate code as data and vice versa, enabling you to create powerful macros and customize the language to your needs.

3. Problem-Solving Abilities: Lisp's expressive syntax and powerful features help develop your problem-solving skills and encourage innovative solutions.

4. Understanding of Language Design: Lisp's simplicity and extensibility offer insights into language design principles, making you a better programmer overall.