It’s easy enough to play with a box of Lego bricks and figure out how they stack on top of one another. However, as you begin to use more advanced techniques and connections, you won’t be able to fully appreciate and use them until you understand some basic Lego geometry.

Let’s look at the one Lego piece that serves as the foundation for the entire system. **All Lego parts are based on the measurements of this one part.** This is why all Lego pieces connect to all other Lego pieces, making Lego one big system instead of a bunch of random plastic shapes. See, I told you it was important.

This is the 1×1 brick. The bump on top of the brick is called a **stud**. However, the term *stud* is also a measurement equal to the width of a 1×1 brick. The top of a 1×1 brick is perfectly square; it is one stud wide and one stud long.

Here’s where it gets a little tricky. Despite common belief, **Lego bricks are not perfect cubes**. The 1×1 brick is taller than it is wide and long. It is 1 1/5 stud high. 1 1/5 stud high is one brick high. Like *stud*, *brick* has multiple meanings, including a measurement.

It’s time to introduce another important Lego piece- the 1×1 plate. Like the 1×1 brick, it is one stud wide and one stud long. However, it is 2/5 studs high. 2/5 studs is- you guessed it!- a plate. **Three plates stack up to be the exact same height as a brick.**

Often, when building, you can use parts with their studs facing sideways. (This is often referred to by Lego fans as SNOT, Studs Not On Top.) When doing so, it’s often easiest to just remember that **five plates equal two studs.**

An actual stud (bump) is one half of a plate high, or 1/5 stud (length). Although you won’t have to know this as often as other measurements, it is good to keep in mind as you start to make more complex creations.

**Let’s summarize:**

All measurements and connections of Lego pieces are based on the dimensions of the 1×1 brick. This makes Lego parts a system.

**Stud:** the width of a 1×1 brick or plate. It is equal to:

- 5/6 of a Brick
- 2 ½ plates

**Brick:** The height of a 1×1 brick. It is equal to:

- 1 1/5 Studs
- 3 Plates

**Plate:** The height of a 1×1 plate. It is equal to:

- 2/5 of a Stud
- 1/3 of a Brick

**The two most useful things to remember:** Always remember that **3 plates equal a brick** and **5 plates equal 2 studs**!