Why is it so important?

What types of play are best for my child?

It depends on the stage of development. Since play is the tool your child uses to learn about the world, the skills she's working on right now are your biggest clues to choosing the best activities. For instance, if your 12-month-old is exploring cause and effect, play a simple version of hide-and-seek under tables and chairs. If at 20 months she's obsessed with climbing stairs, find a set where she can practice under your watchful eye.

Here are some guidelines for the types of play your child may be most interested in at different stages, according to Catherine Marchant, a play therapist at Wheelock College in Boston:

Social play
Interacting with you and others is important throughout the first year. Infants like to smile, look, and laugh. Older babies enjoy games such as peekaboo and itsy-bitsy spider.

Object play
Touching, banging, mouthing, throwing, pushing, and otherwise experimenting with things is fascinating for the 4- to 10-month-old set.

Functional and representational play
Pretending to use familiar objects in an appropriate way — pushing a toy lawn mower over the grass, or calling Grandma with a hairbrush, for instance — is the height of fun for 12- to 21-month-olds as their imaginations begin to blossom.

Early symbolic play
This type of play, common around the age of 2, creates something out of nothing. Your child might play with a shoebox as if it were a school bus, complete with motor noises, for example, or pretend to eat a plastic ring, insisting it's a doughnut.

Role play
Around 30 to 36 months your little actor will begin taking on new roles. Playing doctor, teacher, or mommy is common now.

How can I make the most of my child's playtime?

Try these suggestions:

Think of playtime as more than toy time. Playing is really any enjoyable activity that involves people, objects, or movement. Everything from blowing bubbles at each other to singing songs to splashing in the tub to chasing each other around the room qualifies. If you've ever seen a 1-year-old enthralled with a cardboard box, you understand how wide the parameters are.

Play along with your child. You're the ultimate plaything, and any activity will seem more fun if your toddler can share it with you. Talk to her while you play and you'll help boost her language skills.

Introduce play activities when your child is happy and rested, suggests Marilyn Segal, a developmental psychologist and author of the Your Child at Play series.

Stop when your child's had enough. Children have different thresholds for stimulation. When yours seems bored, fussy, or tired, it's time for a break.

Give your child a chance to play alone and with others. Both types of play are beneficial.

Let your child choose activities and control the direction of her play. You can suggest new things or present new options, but your child should be the boss. After all, play is about fun, and if there's one thing your child is an expert at already, it's having a good time.