Which cause us to change the small letters to capital?

THE  CAPITAL LETTER  STARTING FROM BEGINNING OF PARAGRAPH

capitalize rules tend to vary by language and can be quite complicated. it is widely understood that the first word of the sentence and all proper nouns are always capitalized 

By the Shift button on the Keyboard you can Capitalize the word. The words are usually capitalized in the beginning of the sentences or after full stops. 

Use shift to capitalized the first letter.

By shift button on the keyboard

During the beginning of the sentence, when its a name or a modified item, or during the high lightening of the word

CLICK THE SHIFT BUTTON ON THE KEYBOARD

When a word is a Proper noun, we change small letters to capital.