What is patch?
1)Patch is nothing but updated or enhanced version of installed software (binary file or library collection) which update the software, in order to increase the:
a. Stability
b. Performance
c. Bug fix
d. New features into system.

2) Visit the site SunSolve to download or to find out the patch reports.

3) Each patch has unique patch number followed by revision number for e.g. 111112-03

To Displays a list of the patches currently applied:
1) Use the command patchadd –p as follows:
# patchadd –p
OR
# showrev -p

How to add or install patch to system?
1) Download the patch from suns web site.

2) Unzip the patch by running command:
#unzip 111307-04.zip

3 Apply the patch as follows:
# patchadd 111307-04

Checking installed patches…
Verifying sufficient filesystem capacity (dry run method)…
Installing patch packages…

Patch number 111307-04 has been successfully installed.
See /var/sadm/patch/111307-04/log for details

4) Reboot the system

To remove the patch:
1) Simply run command patchrm
# patchrm 111112-03

How to install the patch without backing up current file (use with caution)?
1) Use –d switch to patchadd command
# patchadd –d 111112-03