Here is a map of the Big Island:
The west side of the island is dry, hot, and very black from the lava flows from Mauna Loa and Hualalai. Because there is so much lava, the sun heats the lava up in the morning, and the rising heat draws in the cool ocean air, causing windy afternoons.
The other side of the island, however, gets a lot of rain. The city of Hilo can get up to 280 inches of rain a year! Since that area is so wet, orchids, bananas, and macadamia nuts are grown over there.
This island is the newest island of the island chain, and is constantly grows each day by the eruption of the Kilauea volcano, located on the southeast side of the island.
The main resort areas are on the west side, of course, even though the views are not the greatest. Most people want the sun over green anyway - that's why they came to Hawai'i. The only side to show any erosion is on the northeast side, which contains seven valleys that have dramatic 1,000 foot waterfalls. Most of the area near the sea is very cliffy, some of which was caused by a large tsunami in 1946.