The problem asks to evaluate the expression $4^{-1}$.

1. Problem Description

The problem asks to evaluate the expression $4^{-1}$.

2. Solution Steps

A negative exponent indicates the reciprocal of the base raised to the positive exponent. That is:

$a^{-n} = \frac{1}{a^n}$

Using this rule, we can rewrite $4^{-1}$ as:

$4^{-1} = \frac{1}{4^1}$

Since any number raised to the power of 1 is just the number itself:

$4^1 = 4$

Therefore:

$4^{-1} = \frac{1}{4}$

3. Final Answer

The final answer is $\frac{1}{4}$.