Entropy can mean different things: Computing In computing, entropy is the randomness collected by an operating system or application for use in cryptography or other uses that require random data. This randomness is often collected from hardware sources, either pre-existing ones such as mouse movements or specially provided randomness generators. Information theory In information theory, … Read more
It is much harder to build components that use more than two states/levels/whatever. For example, the transistors used in logic are either closed and don’t conduct at all, or wide open. Having them half open would require much more precision and use extra power. Nevertheless, sometimes more states are used for packing more data, but … Read more
Take a look at this blog post by Steve Yegge (formerly of Amazon, now at Google): The Five Essential Phone Screen Questions It goes into some detail about the the five most important concepts that developers should be required to know: Basic programming (including recursion, file I/O, formatted output, loops etc) Object oriented design (including … Read more
A predicate (‘PRED-i-cat’) is the part of a sentence that contains the verb and tells you something about the subject. For instance, in the sentence “Mike is eating”, we have the subject, ‘Mike’, and the predicate, ‘is eating’. In the context of computer science, we aren’t interested in stating a fact, but rather, in testing … Read more
P stands for polynomial time. NP stands for non-deterministic polynomial time. Definitions: Polynomial time means that the complexity of the algorithm is O(n^k), where n is the size of your data (e. g. number of elements in a list to be sorted), and k is a constant. Complexity is time measured in the number of … Read more
I assume that you are looking for intuitive definitions, since the technical definitions require quite some time to understand. First of all, let’s remember a preliminary needed concept to understand those definitions. Decision problem: A problem with a yes or no answer. Now, let us define those complexity classes. P P is a complexity class … Read more