Suppose you are writing a for or while loop and you want to exit from the particular iteration of a loop or completely, in that case break and continue will be useful.

If you want to exit the loop completely once a certain condition is met, then you break.

For example - 

var = "BeingSkilled"

for a in var:
    if a == "S":
        break
    print(a)

Output - 

B
e
i
n
g

The execution stopped at S as that was the condition for break. 

If you don't want to break free the loop completely but want to skip ahead to next iteration of the loop, then you can use continue for that.

var = "BeingSkilled"

for a in var:
    if a == "S":
        continue
    print(a)

Output - 

B
e
i
n
g
k
i
l
l
e
d

As you can observe, the loop has skilled printing S -- this is due to continue which made it skip ahead from S once the condition matched.