These terms are used when we are selecting items from a larger pool: for example, cards from a deck.

When we select with replacement, we select the first card from a full deck, perhaps look at it or write it down, then put it back in the deck and reshuffle. The second card is also selected from a full deck, and so is each subsequent card. All choices are equivalent and independent.

By contrast, selecting without replacement is what happens in real card games, such as poker. We select one card from the full deck, and perhaps deal it to someone or lay it aside. Then, the second card is selected from a deck of only 51 cards. The third is selected from a deck of 50 cards, the fourth, from 49, etc. etc. Each choice influences the probabilities of all subsequent choices, so they definitely are not independent when we are selecting without replacement.