This lecture focus to describe on Algebraic Expression. Algebraic expression is a group of numbers, symbols, and variables that express an operation or a series of operations. An algebraic expression is an expression built up from integer constants, variables, and the algebraic operations (addition, subtraction, multiplication, division and exponentiation etc.). Variable – A variable is a letter or symbol that represents a number (unknown quantity). A variable can use any letter of the alphabet. Example: n + 5; x – 7; w – 25 etc.