Step 1: Picture the cube as stacked layers.
Since every edge is cut into 3 equal parts, picture the big cube as 3 flat layers stacked one above the other, a bottom layer, a middle layer and a top layer, each layer being one unit thick.
Step 2: Count the small cubes in a single layer.
Look straight down at just one layer. Because each edge is divided into 3 parts, that layer looks like a flat 3 by 3 grid of small cubes when seen from above, which gives $3 \times 3 = 9$ small cubes in one layer.
Step 3: Multiply by the number of layers.
There are 3 such layers in total, and each one holds 9 small cubes, so the total count is
\[ 9 \times 3 = 27 \]
This layer by layer count lands on the same number as the direct $3^3$ calculation, which confirms the answer is correct.
Final Answer:
The cube is cut into 27 smaller cubes.
\[ \boxed{27} \]