Real+ (stylized as REAL+) is the fourth Korean-language extended play (EP) by South Korean singer-songwriter and actress IU. It was released and distributed by LOEN Entertainment on February 16, 2011. The CD, a follow-up to Real (2010), consists of three tracks in total. One song in the album, "Only I Didn't Know", appears twice – the second time as a collaboration piece with pianist .

The music video for the lead track, "Only I Didn't Know" (Hangul: 나만 몰랐던 이야기; RR: Naman Mollatdeon Iyagi), features actress Park Bo-young as she is caught in a dramatic break-up story. Her ex-lover is played by singer-songwriter Yoon Sang, who also composed this piece as a gift for IU. The music video was released on the same day as the album.

The song itself is a departure from the pop-like sounds of her previously promoted song, "Good Day" (Hangul: 좋은 날; RR: Joeun Nal). It features mature vocals and a combination of piano and string instruments.

IU made her promotional comeback with "Only I Didn't Know" in the television show Music Bank (KBS) on February 18, 2011, two days after the album's release.

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