1. To like (to be pleasing)
Gustar
To like
(to be pleasing)

2. Notes Gustar is a Spanish verb we use to express what we like.
It is NOT used as other verbs are, because its literal translation in English is “to be pleasing,” NOT “to like.”
For example: 
Me gustan los perros.
In English would be: I like the dogs.
But really says The dogs (they) are pleasing to me.

3. Notes continued
Because of this, we conjugate gustar NOT based on the subject of the sentence, but based on what it is that is pleasing (that is liked).
In the example above, gustar is conjugated in the third person plural to reflect the group of dogs that are liked.
Me gustan los perros.
I like the dogs.
(The dogs are pleasing to me.)

4. Liking activities
You can also use gustar to talk about things you like to do.
Me gusta comer una merienda.
I like to eat a snack.
(Eating a snack is pleasing to me).
Me gusta jugar al fútbol.
I like to play soccer.
(Playing soccer is pleasing to me)
Things you like to do

5. Liking one thing
In the previous examples, gustar is used as “gusta” because only ONE thing is liked.
Me gusta comer una merienda.
I like to eat a snack.
(Eating a snack is pleasing to me).

6. Liking more than one thing
HOWEVER, if MORE than one thing is liked, you use gustan.
Me gustan los perros.
I like the dogs.
(The dogs are pleasing to me.)
**Gustar changed not because the subject (I) changed, but because the number/amount of things liked changed.
Number/amount.