surf 101 glossary of terms

Surf 101 Glossary of Terms

Looking to buy a new board. Here are some key term to to learn. Our Surf 101 glossary will be the perfect crash course into finding out what to look for and why when buying your next surfboard.

BlankSurfboard Blanks Island Water Sports surf 101 glossary of terms
Rough molded foam core that comes in different basic designs and rockers depending on the length and type of surfboard being shaped. Usually made from polyurethane foam. Surf 101 Glossary


Bottom Contour

The lateral curve of the bottom of the board as it runs from rail to rail. Can be flat, concave, conveyor a combination. Surf 101 Glossary

Carbon Fiber Island Water Sports surf 101 glossary of termsCarbon Fiber

A strong compound, shakable in resin, is occasionally laid in strips along the length, rails, or tails of a board during glassing to help prevent creasing. Surf 101 Glossary


Channelschannels Island Water Sports surf 101 glossary of terms

The channel surfboard bottom consists of flat planes that are designed in a concave configuration. Since the channels sit side by side the water is not being compressed as it is in a full concave, and each channel propel water down the back underbelly of the surfboard and convert this into forward thrust. Longer and deeper channels give a more pronounced effect. Surf 101 Glossary



The main purpose of concave is to channel the water flow down the length of the surfboard. This channeling of the water along the center of the board and out through the tail adds more lift and responsiveness to the surfboard. Concaves are a very important design feature and can cause a board to track swiftly and improve tail responsiveness for critical turns. Surf 101 Glossary

surf 101 glossary of terms


The effect that causes water flow to be slowed or disrupted as it passes along a surfboard’s surfaces. Controlled drag is an essential requirement of surfboard design. Surf 101 Glossary


The result of water passing along the bottom surface of a surfboard, causing acceleration along the face of the wave. A key factor for control and direction, affected heavily by choice of fin setup. Surf 101 Glossary


Type of plastic resin used by some manufacturers in place of polyester resin. Usually an epoxy-user also uses a polystyrene blank, which can be badly affected by polyester resins. Known for its durability. Surf 101 Glossary

Expanded Polystyrene or EPS

A type of foam also known as styrofoam or bead foam. Polystyrene beads are expanded by steam in a mold with desired density determined by quantity of beads expanded within that mold. Surf 101 Glossary


The distribution of foam from nose to tail on a surfboard. For the board to flow correctly, it must be evenly balanced through the shape. If there is excessive foam left in the nose, center, or tail, it will create uneven flow and cause the surfboard to be unbalanced. Surf 101 Glossary

Polyurethane or PU

The most common type of foam used in surfboard manufacturing. Usually employed together with polyester resin. Surf 101 Glossary

Shaping Rails surf 101 glossary of terms Island Water SportsRails

The perimeter of the board. There are several different main types of rails which all produce a different effect. Soft and rounded rails make the board slower but easier to handle. Down rails (where the rail comes to an edge toward the bottom of the board) increases speed but makes the board more difficult to turn. Sharper rails promote quick turns but don’t carry momentum as well as fuller rails. Surf 101 Glossary

Types of Rails:

  • Round Rail – a rounded rail looking almost like a complete semi-circle
  • Down Rails – A rail coming to an edge at the bottom of the board
  • Rolled Rails – Down Rails that are rolled under the board
  • Egg Rails – similar to Round Rails more egg shaped
  • 50/50– A description of the point where the bottom of the rail meets the top. This indicates the meeting point is in the middle of the rail.
  • 60/40 – Again, this is a description telling us the rail’s point is slightly lower than center.


The effect that allows water flow to be accelerated as it passes along a surfboard’s surfaces. Release is altered through tail rocker, outline curves, trailing fin edges, and through bottom features, such as concaves and channels. Controlled release (along with its opposite, drag) is essential to successful surfboard design. Surf 101 Glossary


The curve of your surfboard from nose to tail. It can be broken down into different sections such as nose rocker, tail rocker, and center. It affects the flow of water from entry to release. Surf 101 Glossary


The back section of the board. Tails are crucial in determining how a surfboard will function. Increased tail width means greater speed, especially in smaller surf, but less control; narrower tails don’t maneuver as well, but adhere better to the wave face and are ideal for tube riding and big-wave boards. Surf 101 Glossary

surf 101 glossary of terms


The opposite of concave, vee is used to loosen up the tail at high speeds by increasing the rocker at the rail line, making it easier to lean on edge and turn. Surf 101 Glossary

Shop Our Surfboards

Shop online at or Stop in the Store for a HUGE selection of new and used boards. Custom boards also available. Surf 101 Glossary

Sharp Eyed Surfboards 5’8″ Game Changer #32015



Firewire Surfboards 8’2 SubMoon, TimberTek, NuMoon Tail, Demo-8’2


Modern Surfboards 8’0 Blackbird X1 Funshape, Blue Deck Design-Blue-8’0


Channel Islands Surfboards 5’7 New Flyer, 19 3/8″ X 2 5/16″, 2-Tab, Squash Tail-5’7 X 19 3/8″ X 2 5/16″

GSI Ambassador, Richie Lovett, describes the design features of the Modern Surfboards Blackbird in X2 construction now for sale online at Island Water Sports. The Blackbird is part of the GSI range of Modern Surfboards.