Elementary algebra is the most basic form of algebra taught to students. It is often one of the next areas of mathematics taught to students after arithmetic. While in arithmetic only numbers and operators like +, −, ×, and ÷ occur; in algebra, variables (like a, x, y) are used to stand for numbers. This is useful because:

• It lets people solve problems about "unknown" numbers. This means learning about equations and how to solve them (for example, "find a number x where \displaystyle{ 3x + 1 = 10 }").
• It allows the generalization of the rules from arithmetic. While some students understand that \displaystyle{ 3+4 = 4+3 }, it helps to prove that \displaystyle{ a + b = b + a } for all a and b. This makes algebra a good step to learning about abstraction (learning general ideas from many examples).
• It helps people understand and create functional relationships (also sometimes called cause and effect). An example of this is "if x tickets are sold, then the profit will be \displaystyle{ 3x - 10 } dollars".