Concatenation operators

# Use + for strings or lists
'a'+'b'     # 'ab'
[1,2]+[3,4] # [1,2,3,4]

# Use .. to convert the right operand to a string
'a'..1 # 'a1'

# Use .. to modify lists
list=[1,2]
list..3
print(list) # [1, 2, 3]

Basic tips