Slabs are classified into two types: One Way Slab and Two Way Slab.

One way slab is a slab which is supported by beams on the two opposite sides to carry the load along one direction.

Two way slab is a slab supported by beams on all the four sides and the loads are carried by the supports along both directions, it is known as two way slab. In two way slab, the ratio of longer span (l) to shorter span (b) is less than 2.

**Difference between OneWay Slab and Two-way slab:**

One Way Slab |
Two Way Slab |

Slabs are supported by the beams on the two opposite sides | Slabs are supported by beams on all the four sides. |

Main Reinforcement is provided in only direction for one way slabs | Main Reinforcement is provided along both the directions in two way slabs. |

Loads are carried along one direction in one way slab. | Loads are carried along both the directions in two way slabs. |