Birth to 1 year: 1  In the early months, hold your baby close and read, talk and sing to her. 2  By 3-6 months of age, your baby will start to enjoy looking at mirrors and pictures of faces, shapes, colors.  By 6-12 months of age, your baby will sit in your lap, look at the pictures, touch the book, and put the book in her mouth.
From Wikipedia, the free encyclopedia. Sigma 30mm f/1.4 EX DC HSM mounted on a Canon EOS 40D, hood attached. The Sigma 30mm f/1.4 EX DC HSM is a wide-aperture photographic lens made by the Sigma Corporation, equipped with Hyper Sonic Motor (abbreviated HSM, Sigma's trade name for photo lens focusing technology using ultrasonic motor).
Sigma is the 18th letter of the Greek alphabet and is equivalent to our letter 'S'. In mathematics, the upper case sigma is used for the summation notation. The lower case sigma stands for standard deviation. Each has its own unique formula, and yes, both the upper case and lower case look vastly different from each other.