The modal verbs can and could represent the ability of a person or thing in doing something. However, there is a difference in their usage, as ‘can‘ is used in present situation, whereas we can use ‘could‘ for talking about a past ability. Both are followed by a base form of the verb. Now look at the example given below to understand their difference in a better way:

So in these two cases, you might have observed that can is used to represent present condition of the subject, but could is used to reflect a past ability, as could is nothing but a past form of can.

In simple words, ‘can’ means to be able or permitted to do something. It is used with the first form or the base form of the verb. Basically, it determines the ability or capability of someone or something. It has several uses as discussed below:

Could is the past participle form of the verb ‘can‘ which determines the past ability of someone or something. It is also used when someone is permitted to do something. Now let’s discuss where we can use ‘could’ in our sentences:

The difference between can and could, are described in the points given below:

Can

Could

The words can and could are often juxtaposed, as they are the forms of the verb ‘can’. You should remember that you can use ‘can’ or when you are talking about present ability and possibility or when you are requesting or offering something to your friends, relatives and acquaintances. Similarly, you can use ‘could’  when you discuss about the past ability or possibility or when you are requesting or asking something to ‘strangers’.