In manual Testing, few reviews are there. test plan review, 
testcases review, test scenarioes, coding review, bug 
review...

for example once the tester complets writing testcases, 
some senior person have to review that testcases document 
and they have to review that whether testcases are correct 
or wrong.

correct me if i am wrong...

Review is a process or meeting where we check the
correctness of the documents based on the organization
standard. Are we following the right coding standard, right
test case preparation methods or template. 
Primarily, reviews can be divided into two parts:
Formal review
Informal review: code review, peer review, walkthrough
Formal review: inspection, 

Formal review has defined entry and exit criteria, done in a
very formal way with moderator, and all
Informal is just a friendly way of checking the documents
that covers requirements, should be correct as per the
standard defined by the organizational process.