Smith is an Agent, an artificial intelligence manifested in the Matrix and possesses extraordinary powers to manipulate his surroundings (including superhuman strength and the ability to flawlessly dodge incoming bullets). However, Agents still have limitations, being "based in a world that is built on rules". Consequently, he cannot fly, walk through walls, or perform any other actions outside the boundaries of his programming.
Agent Smith is played by Hugo Weaving and I must say, the casting was spot on coz he was really annoying in the film, behaving like he owned everyone.
Hugo Weaving's performance as the enigmatic Agent Smith earned him international recognition. He would reprise the role of Smith in the sequels: The Matrix Reloaded and The Matrix Revolutions. He also garnered much popular attention in the role of the Elven Lord, Elrond in The Lord of the Rings, as V in V for Vendetta and as the voice of Megatron in Transformers.
The fear on his face at the end of The Matrix when he saw Neo stop bullets was priceless. And how the other Agents ran!