Play: The Basics

What Is Play?

Play is state of mind that one has when absorbed in an activity that provides enjoyment and a suspension of sense of time. And play is self-motivated so you want to do it again and again.

Dr. Stuart Brown (p. 60)


The characteristics of play all have to do with motivation and mental attitude, not with … the behavior itself. Two people might be throwing a ball ... or typing words on a computer, and one might be playing while the other is not. To tell which one is playing … you have to infer from their expressions and the details of their actions.

Peter Gray (p. 139)

Do You Know Play When You See It?

A man smiles as he admires his extensive coin collection.

On the surface, a person at play looks lost in the moment, absorbed in what they’re doing, focused on the activity without paying attention to anything else. You might not know that evolution provided the biology enabling these simple, rich pleasures.

Play Is a State of Being

Three young children playing ring-around-the-rosie
Older adults laughing over a card game

When players become engrossed, time seems to stop. They might say they’re having fun, relaxing, or in the zone. We call this feeling “the play state.”

The play state begins in the midbrain, like hunger, fear, and caring. When you encounter something playful, neurons in your midbrain light up. They start a cascade of connections that light up neurons across the brain and create a play state. This is what we mean when we say “play lights up the brain.” Learn more about the biology of the play state.

Our Play Is Unique to Us

The situations that trigger our play states are individual preferences determined by our brain wiring at birth and our early life experiences. Your play state may be triggered by an object, another person, an activity, or a combination of these; the triggers are different for everyone. If two people are doing the same activity, it could be playful for one and not the other. There are many  triggers that are common to most everyone, we all respond positively to a welcoming smile or a tail wagging puppy — those are brief playful moments.

Play is not necessarily all or none. Play can [exist] from zero up to 100 percent … the adjective playful is often more useful than the noun play, which tends to be interpreted as all or none. People can, to varying degrees, bring a ‘playful attitude’ or ‘playful spirit’ to [a situation] … pure play (100 percent playful) is more common in children than in adults. … We don’t have metrics for these things, but I would estimate that my behavior in writing this book is about 80 percent play. That percentage varies … it decreases when I worry about deadlines or how critics will evaluate it, and it increases when I’m focused only on the current task of researching or writing.

Peter Gray (p. 140)
An older couple laughing as they to the next hole with their golf clubs.
Golf is play for this couple.
A man angrily swings his club at the rough along a golf course.
Golf is not play for this guy.

The opposite of Play is not work, it’s depression.

Brian Sutton-Smith

Play Is Critical for Children

Very few of the neurons in the upper brain (our cortex) are connected at birth; it takes activation from the environment to create connections. Play is a way to establish new connections; it primes the cortex for the development of the neural pathways that create our physical, social-emotional, and cognitive capabilities. So, the more often children are in a play state, the more new brain circuits form and build their skills. Playing literally wires the brain for the skills we use our whole lifetime — physical agility, social confidence, emotional regulation,  creativity, and resilience.  As adults, time spent in a play state increases our resilience — it activates neural pathways in the brain that mitigate the effects of stress.

Infants' brains build connections quickly, from mostly isolated neurons at birth to a dense web of synapses by 24 months.
Source: Conel, J. L. (1939–1967). The Postnatal Development of the Human Cerebral Cortex. Cambridge, MA: Harvard University Press.

Neurons that fire together, wire together.

Donald Hebb

Terminology of Play

Play has been scientifically studied and shown to contribute to the optimal development and stable well-being of humans throughout life. Here we explain how scientists define what play is, the characteristics of the activities that offer those benefits to children, adolescents, young and old adults.

Free Play

A boy jumping off a picnic table to bellyflop into a huge pile of leaves.
Free Play

Play (Free Play) is an activity someone chooses for themselves simply because they want to do it—that is, the activity is intrinsically motivated.  The person is doing the activity for the internal satisfaction experienced from the activity – versus doing the activity for an external reward e.g., money or to gain someone’s approval. Scientists say play is a self-selected, self-directed activity that is structured by the player. On this site we call this simply “play”, or “free play” – because play is freely chosen by the players. 

Play is an activity that is 100% playful. Children, unencumbered by life responsibilities, easily reach the state of free play. Look at the boy jumping over a pile of leaves, he is in a 100% totally engaged, playful state that he chose and that he is directing. That is free play. 

A key point here is that activities that are directed by another person and activities that we pursue for an external (vs internal) reward, are not play.  They may be to varying degrees playful, but they are not, by objective definition, play or free play.

NIFP and Dr. Brown reserve the word “play” for an activity that includes all of Dr. Peter Gray’s (p.140) five elements of play:

  1. Self-chosen and self-directed;
  2. Intrinsically motivated (that is, the means are more valued than the ends);
  3. Structured or ordered based on rules in the player’s mind;
  4. Imaginative, or has a creative aspect); and
  5. A playful state of mind—the player is very engaged, alert, mentally active, and focused on the activity, but is not stressed about the activity (they have no fear of judgment, and there are no consequences that matter outside of the activity itself).
    More on definition of play by Dr. Gray

Free play is most common in children; they are far less constrained by the responsibilities that accumulate as we grow older. In free play, children follow what naturally engages them. Children playing are doing things they are innately motivated to do -activities they just want to do; because their chosen activities are innately motivated, they want to do them over and over.

In adults, playfulness most often blends with other attitudes and motivations having to do with adult responsibilities. Adult activities can be quite playful, and there can be a great deal of internal satisfaction felt from those activities.  However adults seldom if ever get to the 100% playful state that happens so often in childhood. 

The degree to which an activity is engaging, self-chosen, self-directed, internally motivated and internally rewarding contributes to a subjective sense of how playful the activity is.  An activity that meets all five of the above criteria fully is 100% playful or what we call play.  Now there are not objective, repeatably measurable metrics for these factors (yet), but generally if an activity meets many of them and it is something that one wants to do again and again, then those activities put us in what Dr. Brown calls a “state of play.”

A gradeschooler and her preschool-aged sister playing on a tablet together.
Mixed Age Play

Play can be solitary (reading, collecting or creating), or social.  Groups of players may be of similar ages or skill levels (children jumping rope or adults playing bridge). When children of different ages or skill levels are playing together,  we refer to it as “mixed-age play”

Mixed-age play is qualitatively different from same-age play. In mixed-age play each child tries to do their best but has little or no concern for beating others. Mixed-age play enables younger kids to learn skills and more sophisticated ways of doing things from older kids. In turn, the older children benefit from learning how to nurture, lead, and be the mature person in a relationship (Gray pp. 35 & 181-186). With adults who are playing, mixed skill levels enable the less skilled adults to learn from those more skilled.

When multiple children are involved, free play involves consensus of choices on the activity and the structure of the activity. Anyone participating without feeling in agreement with the rules isn’t fully engaged and not really playing.  More on mixed-age play.

An activity stops being play for the participants the moment a non-participant (e.g., an adult) questions the players’ choices or outright directs the activity.

Free play is critical to healthy development of children, especially young children. For adults, play and playfulness are central to equanimity and well-being.

Directed Playful Activities

An adult preschool worker guiding an excited boy leap from block to block.
Adult Directed Play

Children’s activities directed by an adult can be playful and fun, but since they are not self-chosen or self-directed they are not fully play. Those who experience an activity directed by someone else as playful are engaged in the activity; those who do not experience playfulness during the activity are most likely not bought in, not engaged in the activity. 

Examples of directed playful activities include playful classroom lessons led by teachers to facilitate learning and recess or after-school activities organized by teachers or other adults. These activities can be fun, may develop the social-emotional skills of the children participating, and can create a sense of belonging for the children that fully buy in (are engaged by the activity). But these activities are not self-chosen and self-directed and some children will not be engaged in them; for those children the activity is not playful let alone play. Children not engaged and playfully participating in the activity will not accrue the learning, SEL (socio-emotional learning) and belonging benefits that those who are engaged receive. More on adult directed activities by Dr. Gray