Capitalism can be simply defined in the following aspects:
1. An economy characterized as consensual trade between parties.
2. An economy in which power over the means of production is concentrated in the hands of private owners who make up a class of proprietors, characterized by private property and the commodification of human labor.
3. The symbiotic relationship between business enterprises and the government in order to protect property and the class of proprietors.
Note that anti-capitalism can be simply defined as an economic philosophy that opposes at least the second and third aspects of capitalism (and possibly the first in the case of a communist gift economy, that focuses on distribution rather than marketplace trade). While capitalism is often heralded as a philosophy of freedom, there are numerous aspects which hinder the well-being and rights of the individual and prove fundamentally incorrect.
1. Property: anti-capitalism supports the notion of use and occupy, which recognizes that ownership of property is only truly legitimate when it is combined with the labor of the individual who claims ownership of it. The person who owns land/property must be the person who has labored to create it, in order to maintain the principle of self-ownership. 
In order to acquire ownership of land in a morally permissible manner, one must combine their own labor with that of the land, which belonged to no one previously since it is entirely independent of any labor, to be able to legitimately occupy it. However, under capitalism, one does not have to utilize property to maintain ownership of it, since the title is protected by the state. One can lay claim to any piece of land, and maintain it by force, even if no labor has gone to obtain it.
The ownership of natural resources extracted from the Earth, such as water, air, and land, should not be regarded as private property, since everyone needs those resources to survive and because no one labored to produce those resources; it would be unjust to grant them an arbitrary title of ownership over something that has existed for centuries without deriving from the work or labor of any one person. No one is entitled to resources which are independent of their own creation; they belong to the Earth, not to whichever proprietor uses the most violence to obtain them. One can only occupy land or property through the combination of labor, but can never claim private ownership of something entirely independent of their labor, or which had been abandoned and lacks the presence of their labor.
2. Profit: anti-capitalist philosophy maintains that the means of production should belong to the workers that utilize them. This is closely intertwined with the view on property: property which lacks the labor of its owner is not legitimate, but a baseless claim. Under capitalism, a boss merely has to maintain the claim of private property over the means of production to extract labor from the hired workers. Despite the fact that all value produced by the means of production results from the worker’s labor, the boss still claims the right to a large portion of the worker’s labor due to the claim of private property. Anti-capitalism holds, however, that workers are entitled to the full value of their labor; labor is entitled to all that it creates. For this reason, anti-capitalism supports the notion of worker control over the means of production, since it is not the labor of the boss but the labor of the workers that is combined with property to equate ownership, and it is not the work of the boss but of their workers that produces value. Labor is the source of all value, and is essential to distinguish the owner of property. Proprietors who abandon property or do not utilize property for personal production are not entitled to the labor of others in the form of profit.