Face to Face Interviews:-

The face-to-face interview, also called an in-person interview, is probably the most popular and oldest form of survey data collection. It has continued to be the best form of data collection when one wants to minimize non response and maximize the quality of the data collected. Face-to-face interviews are often used to solicit information in projects that can be considered to be very sensitive. The main advantage of the face-to-face interview is the presence of the interviewer, which makes it easier for the respondent to either clarify answers or ask for clarification for some of the items on the questionnaire. Sometimes, interviewers can use visual aids (e.g. so-called show cards/Logo Card/Pack shots/Ad stills) to assist respondents in making a decision or choice.

It is the standard of the face-to-face data collection methods (in international research terminology: Paper and Pen Interviewing). Questionnaires are finished in a printed form and the interviewers complete them with a pen according to the answers of the respondent.
CAPI stands for "Computer-Assisted personal interview".It is an interviewing technique in which the respondent or interviewer uses a computer to answer the questions. It has been classified as a personal interviewing technique because an interviewer is usually present to serve as a host and to guide the respondent.
CAWI stands for "Computer-Aided Web Interview". It refers to an online survey administration system the interviewees answer the questionnaires using the Internet. It is a Internet surveying technique in which the interviewer follows a script provided in a website
PAPI has been replaced by methods CAPI/CAWI to an increasingly great extent recently due to the development and spreading of IT techniques.
Due to this interviewing deadlines are reduced, results become more credible and the price-value ratio improves, too. Presenting multimedia materials becomes simpler and becomes a reality, since laptops are able to play films, present pictures and play audio files.
Each interviewer works with a secure laptop by the help of which data can be browsed in a quick and safe way.
The logical relationships between answers are controlled by a scripting program. If the interviewer ticks an answer that was not allowed by the research when drafting the questionnaire, the program does not let the interviewer go on, but warns them to tick another answer.
Each answer will be stored automatically during the interviewing and these form the data file summarizing the results at the end of the interview. Since data are entered immediately, there is no need for manual data entry. The interviewer should only connect to the main server and load in the collected data.