Most modern packs have an insert for sliding hydration bladders through which you suck water from a tube.Others prefer to carry liquids in a bottle inside the pack or in a side pocket within easy reach. Bladders come in a variety of shapes, sizes and designs offer ther most lightweight means of carrying liquids .

An essential item, for day walks as well as multi-day trips. Headtorches tend to be used more by walkers than hand-held torches and a wide range is available.

GPS receivers, digital locators and mini weather stations are all becoming more and more popular. Sometimes you get them all in a small wristwatch!

Cameras and bags from everything from multi-lens SLR's to the smallest compact digis.

Trekking poles reduce the jarring experienced in long descents and prevent early wear and tear on the joints. They are also useful for propelling walkers uphill.

Mostly used by climbers but may occasionally be used by hillwalkers when scrambling or abseiling.

Possibly the most despised article of outdoor clothing, but well-fitting gaiters do prevent waters entering your boots through the top. They also prevent your trousers from soaking up water, or getting covered in mud.

Just like Boy Scouts hillwalkers shouldn't leave home without a knife, or one of the multi-tools now available on the market.

Dehydrated or freeze dried, backpacking food has improved enormously over the years, as have the means to cook it.

Anything not covered in the other categories.