I am a developer programmer and my husband is software engineer. We are planning for PR in subclass of 189. I want to know how the questions will be in ACS skill assessment. Is there any link for sample question.
Australian Computer Society (ACS) has several documents on their website that explain the process. I personally don't think they're as clear as they could be, but you should read through them, then ask specific questions here, or better, email ACS if you need clarification.
One landing page is here which has links to a FAQs, topics, checklist.
A very important document is the Skills Assessment Guidelines document here.
From what I can tell, there's no interview and generally no questions on specific skills to answer.
You will need to have a letter that includes your name, dates of employment, job titles and possibly duties from each company that you are using to claim skills.
You will have to provide any educational diplomas plus transcripts if you have educational qualifications. Vendor certifications are also counted.
If you do not have educational qualifications in the field you may have to also fill out detailed reports that describe projects worked on. This is if you are going the "Recognition of Prior Learning" route--only needed if you have no relevant (Information and Communication Technology) ICT tertiary education.
NOTE: As of 21 September 2016, the ACS website says that there will be a new version of the website as of 26 September, so links may no longer work.