Variation in linguistics refers to how people from different regions or social groups speak the same language in different ways. Just like how you might say "water" and your friend might say "wata," people speak the same language but use different pronunciations, vocabulary, and grammar depending on where they come from or who they are talking to.
For example, if you lived in Texas, you might say "y'all" instead of "you all," or "fixin'" instead of "getting ready." These differences in how we use language are called variations.
Sometimes, people might judge others based on their linguistic variations. For instance, someone may think someone who speaks with a Southern accent sounds uneducated, or someone who speaks with a British accent sounds intelligent. However, it's important to know that these judgments are wrong, and everyone should be respected for the way they speak.