What is the difference between "Aquí", "Ahí", "Allí" and "Allá" and when to use them?

"Aquí", "Ahí", "Allí", and "Allá" are Spanish words used to indicate different levels of distance from the speaker. "Aquí" means "here", referring to something very close to the speaker. "Ahí" denotes "there", used for something that is not within reach but is still visible or relatively close. "Allí" translates to "over there", indicating something that is further away than "Ahí", but still within a certain distance. "Allá" is also "over there" but suggests a much greater distance, often beyond the immediate vicinity. For instance, you might say: 'Mi lápiz está aquí' to mean "My pencil is here", indicating the pencil is very close to you. 'El basurero está ahí' translates as "The bin is there", implying the bin is within sight but not close enough to reach. 'El teléfono está allí' means "The telephone is over there", suggesting the telephone is a bit further away. Lastly, 'La casa de mis abuelos está allá' translates to "My grandparents' house is over there", indicating their house is at a considerable distance.