The number of different detectors available is confusing.

In the main there are three types of Detector

• Non motion detectors, these are those that will give out a ‘continual’ signal when over ,or near a ‘Target’ if the detector is held stationary over that ‘Target’.
   
• Motion Detectors, these are detectors that will only give a signal when moving over a ‘Target’ and will not give a signal if held still over that ‘Target.
   
• Pulse machines, these are generally considered as beach machines and are better on beaches.
  They have a disadvantage of being particularly sensitive to iron

Advice can be confusing, since everyone will have their own pet choices.  Whatever you choose, do not rush out and spend several hundreds of pounds on a new machine.
Most people change their first detector within a short time of beginning, so second hand is often a better start or to borrow several machines and try them out.

Eventually you will have to get your own machine. Having settled on a machine get to know it and its features, stick with it and get to know it, every machine has a learning curve, some are too steep for a beginner. You might want an upgrade later if you can, but many people never exhaust their machines capabilities. There nothing better than a ‘hands on’ experience.

 All machines will have some sort of ‘discrimination’ facility on them.

What is ‘discrimination’?

All detectors will detect all metal within its range when passed over any metal in the ground.
That is; iron, brass, bronze, ‘tin foil’, lead, silver, gold, aluminium.
Each different metal gives out a different signal when excited by the electromagnetic pulses when these are passed over them. That is how detectors work by sending out a elctromagnetic pulse and then detector circuits sense an imbalance due to the presence of metal.
We do not wish to be digging up small iron, or steel nails etc. so these can be ‘discriminated out’ so we do not receive a signal. This leaves us with more than most of us wish to dig, BUT if too much is ‘discriminated out’ we lose the signals that are worthy of digging.
Items which are circular, such as curtain rings, Finger rings, Ring pulls from drink cans, etc. give good signals, as do near circular items like horse shoes which are also quite large and rusty, large rusty pieces of ferrous material, give ‘good ‘signals.
Anything brass will give a ‘good’ signal, this means 12 bore cartridge ends, or an old door knob. Lead gives ‘very good’ signals, old tooth paste tubes. Bottle tops give ‘good’ signals. Pity the bottle has been broken off and consumed. One can go on, in amongst all this rubbish there are a few worth while finds, and its those we are after, the coins, the badges, the pot-mends the horse brasses, sadly these are far between , unless you are lucky.

Ask any detectorist were he would be if he had a £ for every lb of trash they had picked up in a days detecting and the reply would be “In credit!”