CUBE MECHANISM

A Rubik's cube consists of 26 pieces. Following are the types of pieces:

1. Corner pieces
2. Edge pieces
3. Centre pieces

CORNER PIECES

A cube comprises of 8 corner pieces. They have three colored faces. A corner can only be swapped with another corner piece. It is impossible to swap a corner with an edge or a centre piece.

EDGE PIECES

There are 12 edge pieces in a cube. They have two colored faces. An edge can only be swapped with any other edge piece. You cannot move an edge to a corner's or a centre's position.

CENTRE PIECES

A rubik's cube has 6 faces and 6 centres embedded in each face. They have only one colored face. Centre pieces denote the color of a particular face/side/layer. A centre can only be swapped with any other centre piece on the cube.

FINGERTRICKS

Rotating the upper layer using both index fingers.

You might be solving a cube by rotating the sides using your complete hand. This eventually reduces your speed and therefore increasing your time. For an effective solve you must use your fingers instead of complete hand. Fingertricks would enable you to reduce you time and once you are in practice there would be a drastic change in your time and efficiency.

• Use the index fingers to rotate the upper/top layer clockwise and anticlockwise.
• Use the middle fingers to rotate the middle layers.
• Use the ring/third finger to rotate the last/lower/bottom layer.
• Use the whole hand while rotating both left and right layers.
• Use the index fingers to rotate the front and back layers.

NOTATIONS

• Before trying to solve the cube you must be aware of the notations used while solving a cube. 

In order to convey a certain turn or a sequence of turns around the cube through writing, there are certain agreed key letters that specify exactly what move should be made: There are 6 different letters for turning the Rubik's cube, each for the 6 faces of the Rubik's cube to be turned:

• F (front): the face facing the solver.
• B (back): the back face.
• R (right): the right face.
• L (left): the left face.
• U (up): the upper face.
• D (down): the face opposite to the upper face.

The letter means turning a single turn, (90°), clockwise, the corresponding face. 

Letter followed by an apostrophe mark (') (known as "prime") means turning the corresponding face a single turn, (90°),counter-clockwise. 

These notation marks will always be in Capital letters. The reason for that is that there are different meanings for small letters.

DOUBLE LAYER TURNS

A small letter means turning the face along with its corresponding middle layer, making it a double layer turn. The reason for doing such moves is that it can reduce the need of cube rotations.

• u: Turning the top 2 layers together.
• r: Turning the right 2 layers together.
• f: Turning the front 2 layers together.
• d: Turning the bottom 2 layers together.
• l: Turning the left 2 layers together.
• b: Turning the back 2 layers together.

Note: u' ,r' ,f' ,d' ,l' and b' mean that turning the specified layers counter clockwise.

A sequence of turns in a row is represented by a sequence of letters, and called an algorithm. 

MIDDLE LAYER TURNS

There are 3 different middle layer possible turns in the Rubik's cube, represented by letters . Only 1 out of the 3 is popular in common algorithms, while the other 2 are rarely used. 

• M (middle): the middle layer parallel to the R & L faces.
• E (equator): the middle layer parallel to the U & D faces.
• S (side): the middle layer parallel to the F & B faces.

CUBE ROTATIONS

A cube rotation is a rotation of the whole cube. Sometimes making a cube rotation allows executing much more convenient turns, like turning the R face, instead of the B face. There are 3 possible axes to rotate the cube on: The x, y & z axes. Best way to remember the rotations is just thinking about a 3D function graph:

• x : rotating the cube on the x axis. (R & L faces remain intact)
• y : rotating the cube on the y axis. (U & D faces remain intact)
• z : rotating the cube on the z axis. (F & B faces remain intact)

Cube rotations can be followed by a prime (') meaning rotating the cube a quarter rotation (90°) on the corresponding axis counter-clockwise.

INTRODUCTION

Professor Erno Rubik

• Rubik's Cube is a 3-D combination puzzle invented in 1974 by Hungarian sculptor and professor of architecture Erno Rubik.
• The cube comprises of 3 horizontal and 3 vertical layers. There are 8 pieces having 3 colors on them, 12 pieces having 2 colors and 6 center pieces which denote the color of each of their corresponding layers.