From your perspective, who do you believe were the "good guys" in World War I?
The Central Powers
Some argue that Germany's behavior during the July Crisis (following the assassination of Franz Ferdinand) was highly militaristic, with Germany encouraging Austria-Hungary to wage war against Serbia (and as a result, France and Russia). Some also point towards Germany's policy of weltpolitik, or aggressive diplomacy, as being responsible for the war.
It should be noted that the Central Powers were accused of war crimes and widespread human rights abuses during the war, leading some to believe they were the "bad guys." One such example is the Ottoman Empire's alleged genocide against Armenians, Assyrians and Greeks. Another example was the Rape of Belgium, in which Germany followed a policy of treating civilians as combatants (either armed or not), killing and plundering across the country. A more controversial example would be Germany's unrestricted submarine warfare, though critics would contend that Germany's unrestricted submarine warfare policy was justified.
The Allied Powers
A common argument is that the Allied Powers were the "good guys," because they were largely democratic and in some ways fighting for the right of central European peoples to self-determination (Czechoslovakia, Poland, Yugoslavia, etc.). Others point to the conflict as a humanitarian one, with the United States helping liberate and rebuild Europe. Many third world nationalists held a positive opinion of the Allied Powers due to Woodrow Wilson's Fourteen Points and calls for the gradual end of European colonialism.
While most contend that the Allied Powers were the "good guys," some believe otherwise, citing Russia's genocide against Jews during the war. Other critics point towards the controversial and potentially "unfair" handling of the Treaty of Versailles and Treaty of Trianon by the Allied Powers (primarily France) as evidence of the Allies (or at least France) behaving in a dishonorable manner. Still others argue that the primary Allied Powers (United States, Britain, France and Russia/USSR) were unfair to their Chinese, Italian, Japanese and Serbian allies following the war.