Aperture Science Handheld Portal Device
The "portal device" is your only tool, and holds immense power. With it, you can create either, or both, ends of a portal, and solve the puzzles. By default, 
will create the blue end of a portal, and 
will create the orange end.
Portals
Portals are the main method of getting around and solving puzzles in Portal, and are either created by the portal gun, or are pre-existing in a chamber. A portal has two ends; a blue end, and an orange end, and you (or objects you send through) can travel between the two in either direction. One of the key features of portals is that momentum is conserved as you go through; if an object is going fast when it enters a portal, it will come out the other end at the same speed, regardless of any re-orientation which might occur. One important practical application of this is to climb up otherwise insurmountable objects: place a one end of a portal at the bottom of a pit, and one facing the top of the object to be scaled, and then fall into the first end of the portal. You will be projected out of the second end and come to rest (if everything's been positioned properly) on top of the previously-insurmountable object.
Chamberlocks
Chamberlocks are the exit points for a chamber, and the objective of each chamber is to reach them. In front of every chamberlock is a field which will vapourise unauthorised material such as
1500MW Aperture Science Heavy-Duty Supercolliding Superbuttons
One of the several devices used to set puzzles in Portal is the superbutton (referred to in this guide simply as a "button", despite the normality such a description implies). They are typically linked to doors with clearly-visible tracks, but require a weight constantly on them to keep doors open; cubes are quite useful for this.
Aperture Science Weighted Storage Cubes
The stereotypical physics block; you can pick them up, move them around, throw them, and – more importantly – leave them on buttons, and push them through portals. They're simply referred to in this guide as "cubes".
Doors
These are – at least to begin with – the main obstacle to progression through the chambers. Typically linked to buttons, doors will only stay open when the button is depressed. The button, or buttons, with which a door is linked can be determined by following the wires from the door to the buttons.