These settings control what is considered a difference in a folder session.
Quick tests
These comparison tests can be performed simply by reading folders and are much quicker than tests that require reading individual files.
Compare file size
Marks files as different if file sizes differ.
Compare timestamps
Compares files' date and time last modified. Timestamps must differ by more seconds than the second tolerance to be considered mismatches.
Ignore daylight saving difference ignores exact hour differences. This is useful for dealing with the way that different file systems handle Daylight Savings Time.
Ignore timezone differences ignores timestamp differences that are multiples of an exact hour.
Compare filename case
Marks files as different if character capitalizations differ.
Compare file attributes 
Archive compares files' archive attribute. Since merely copying a file can change its archive attribute, you should normally disable this option.
System compares files' system attribute.
Hidden compares files' hidden attribute.
Read-only compares files' read-only attribute.
Align filenames with different extensions
Lines up files whose filenames are the same except for the extensions.
Align filenames with different Unicode normalization forms
Lines up files whose filenames are Unicode equivalent.
Tests that require reading files
Compare contents
Enables size or content-related comparisons.
CRC comparison compares files using their CRC values.
Binary comparison compares files byte-by-byte.
Rules-based comparison compares files based on their file format associations. Allows you to ignore differences in line endings, whitespace, or source code comments.
Skip if quick tests indicate files are the same improves comparison speed by only performing the slower, more thorough tests when timestamps are different.
Compare versions
Compares version information, typically stored in application files (.exe, .dll, .ocx, etc).
Override quick test results
Marks files as matching if a content comparison determines they match even if there are differences in timestamps or other quick tests.