Equation involving differences between successive values of a function of a discrete variable (i.e., one defined for a sequence of values that differ by the same amount, usually 1). A function of such a variable is a rule for assigning values in sequence to it. For example, math.f(math.x + 1) = math.xmath.f(math.x) is a difference equation. Methods developed for solving such equations have much in common with methods for solving linear differential equations, which difference equations are often used to approximate.

Learn more about difference equation with a free trial on Britannica.com.

Difference is the contrary of equality, in particular of objects. Differences can only be stated on the basis of a Comparison or categorization. Since a complete comparison of objects or things is seldom possible in practice, only relevant or defining attributes are used for stating equality or difference. Similar objects are only different with respect to attributes of minor discriminative value.

In order for something to be different, you must have something to compare it to.

In particular, difference can refer to:

• In Philosophy, Differance
• In mathematics, difference always means
• the result of subtraction
• difference operator
• finite difference
• percent difference
• difference in set theory: see complement and symmetric difference
• inequality
• Difference in computing: see delta encoding
• Difference on a coat of arms: see heraldry
• Different (song), a song by Acceptance

See also

• Similarity
• Different ideal