What is gorrilla war?

Answer 1

"Guerilla" warfare. Tactics designed to maximise the effectiveness and the survivability of a force (which may be paramilitary or military) that is usually at a disadvantage numerically, and often in terms of firepower, support elements, supplies, infrastructure, technology, and command and control. Such tactics have also been adopted by larger forces for various reasons, often in secondary campaign areas where the concern is more to harry the enemy and deny him control of an area while the bulk of ones forces are committed elsewhere (for instance, the British Commonwealth's Chindit forces operating in South Asia during the Second World War at a time when the War in Europe and North Africa prevented Britain despatching greater forces to India/Burma). The Swiss Army's primary strategy for defending the country from any invasion, which would almost certainly be by far greater forces, calls for guerilla tactics.

The main elements of guerilla warfare are keeping forces broken into small, largelly independent units, which are highly mobile, and try to avoid observation by, or contact with the enemy, except under favourable conditions, and usually relying on surprise attacks and ambushes. Key to success is ensuring the guerilla force is able to choose both the ground and timing of attacks, ideally against small enemy sub-units, far from timely support. After a successful action, the guerilla unit would not normally attempt to hold ground, but quickly escape and evade any possible reinforcements sent to aid the unit they had attacked. The object of guerilla warfare is not to seize or control ground, but to deny the enemy control of the ground, and to tie his forces up in a war of attrition.

It should be noted that this way of fighting has traditionally been relied upon for thousands of years by forces whose numerical disadvantage compelled them to, and where the terrain allowed it. Although such tactics are commonly thought of in connection with heavily forested, or mountainous terrain, they have also been adopted by forces fighting in vast, open terrain, where even a much larger enemy force must spread itself thinly. In such terrain, guerillas are often mounted, allowing themselves to quickly move to attack positions, and to escape and evade a following enemy force as rapidly. Examples include the Scythians in resisting the invasion of Scythia by the Persian Empire, and both Boer and British Commonwealth mounted units during the Second Boer War.

non traditional way of fighting, mostly surprise attacks

Answer 2

I think that "Guerilla warfare" is meant and a description of it can be found here:

http://en.wikipedia.org/wiki/Guerrilla_warfare