|a lot / alot / allot||
A lot, meaning a large amount or number of people or things, can be used to modify a noun.
"I need a lot of time to develop this web site."
It can also be used as an adverb, meaning very much or very often.
"I look a lot like my sister."
It has become a common term in speech; and is increasingly used in writing.
Allot is a verb, which means to give (especially a share of something) for a particular purpose:-
For example: "We were allotted a desk each."
!Note - Alot does not exist! There is no such word in the English language. If you write it this way - imagine me shouting at you - "No Such Word!"