The Russian Nominative Case is used to mark the subject of the sentence.
Like all cases in the Russian language, the easiest way to determine how to use the nominative case is to ask the key questions associated with the case. So, in other words, when you are forming the sentence, first ask yourself the questions:
(1) Who is it? Or...
(2) What is it?
The answer to these questions will tell you who or what is the subject of the sentence. When in the nominative case, nouns do not need to change endings - they use their 'regular' ending.
Below is a table outlining the typical endings used, as well as the relevant endings that apply to any adjectives linked to the noun. Further, we have given some specific examples highlighting the word endings so you can see how the nominative case works.