“I'm lovin' it” was the McDonald's advertising slogan launched internationally in 2003 and commonly presented in a lowercase style.
McDonald's introduced the campaign in Munich, Germany, in September 2003, before expanding it globally. The campaign used the phrase, the “ba da ba ba ba” musical mnemonic, and a contemporary pop-oriented presentation intended to connect the brand with everyday enjoyment.
The English wording uses a contracted form and the informal spelling “lovin'.” That styling helped distinguish the campaign from older, more formal advertising lines. The campaign was created with work from the German agency Heye & Partner and was adapted for markets around the world.
Earlier McDonald's slogans included “You Deserve a Break Today” and “We Love to See You Smile.” Those lines belong to different advertising eras, so they should not be treated as alternate names for the 2003 campaign.