Clovers are an extremely common weed that has a creeping stem with distinctive leaves notched at the tip. Clover heads are often visited by bees. There are two schools of thought one is to get rid of clover in the quest for a perfect lawn and the other is to allow it to thrive. As it a legume if allowed to thrive in your lawn, the clover will put nitrogen into your soil. It will always retain its colour in a drought and you do not need to mow it often as it grows low. It also attracts bees and wasps that feast on harmful bugs and help pollination.
Spray the Clover with a broadleaf herbicide to kill it.