The "poor man's" accelerometer! Tilt sensors are switches that can detect basic motion/orientation. The metal tube has a little metal ball that rolls around in it, when its tilted upright, the ball rolls onto the contacts sticking out of end and shorts them together.
A pin header (or simply header) is a form of electrical connector. It consists of one or more rows of male pins typically spaced 2.54 millimetres (0.1 in) apart, but sometimes 2 millimetres (0.079 in) or 1.27 millimetres (0.05 in) is used as well. The distance between pins is commonly referred as pitch in the electronic community.
Single row of 40-holes, female header with swiss round machined pins. These units have very high quality round pins to accept and retain machine pin headers much better. Can be cut to size with a pair of wire-cutters. Standard .1" spacing. We use them extensively in the Olimex development boards. They mate very well with break away headers.
Drill bits are cutting tools used to create cylindrical holes, almost always of circular cross-section. Drill bits come in many sizes and have many uses. Bits are usually connected to a mechanism, often simply referred to as a drill, which rotates them and provides torque and axial force to create the hole.
Dry film is a polyester film coated with a polymer which is sensitive to ultraviolet light (Photoresist). It adheres by heat to the PCB and allows you to print circuits using any photolithography method. Once photosensitized, it is developed using an alkaline solution.It is widely used at the professional level on the PCB industry.