What are the two types of hypothesis?

There are two fundamental sorts of hypotheses: alternative and null. 

• The alternative theory is also known as the "declarative" theory. A hypothesis is a speculative prediction of how the study will probably turn out. The symbol H1 designates an alternative or declarative hypothesis, which is often expressed positively. It is a claim that makes an inference about a possible result the researcher could anticipate. A declarative or alternative hypothesis is what a researcher formulates when they make affirmative remarks.
• The null hypothesis is often expressed negatively and is indicated by the symbol H0. As it expresses the polarities of what the experiment was designed to expect or anticipate, it is an assertion that there is no real link between the variables. The researcher will either maintain a null hypothesis or discard a null hypothesis in support of an alternate hypothesis in their final report. Acknowledging H0 just indicates that there is insufficient evidence to substantiate it; it does not imply that H0 is correct.