I have a small retail gift store.
I need to know, how many customers are coming to my store each day. I
need some type of automatic machine which will count each person
entering in to the store.
Can someone help to locate such a device or such system

4723...

As with many types of products, there is no perfect traffic counter
for all situations. A lot will depend on your setup, what you can 
afford, and the limitations of different types of counters vs price.

A thorough discussion of the pros and cons of various counter systems
is available on this site that specializes in traffic counting systems
called StoreTraffic.com:
http://www.storetraffic.com/en/information/articles/pf/art003_pf.htm

In the article, the pros and cons, capabilities and limitations of
the major types of counters are discussed in depth, for:

- Light beams
- Passive infra-red detectors
- Proximity detectors
- Cameras
- Radar

Some of these are stand-alone counters, and some are meant to
be integrated into your computer system. Most of them require
that you utilize the services of a professional in setting 
them up and configuring their use in your specific environment,
and training you and/or your staff how to use them.

Naturally, this thorough dissertation is meant to assist you in 
choosing from the products that this site carries, which are on
these pages:

Counters
http://www.storetraffic.com/en/products/counters/index.htm

Sensors
http://www.storetraffic.com/en/products/sensors/index.htm

A new, wireless counter:
http://www.storetraffic.com/en/wireless/FromEntrance.html


Another company that provides products and consultation
is Prodco, though they seem geared up for larger sites:
http://www.prodcotech.com/

Their thermal sensor:
http://www.prodcotech.com/sensors_thermal.html

Their ProStore 5.0 software system:
http://www.prodcotech.com/software_prostore.html


Another site which specializes in traffic counting solutions
is TrafSys.com:
http://www.trafsys.com/


You might even consider using the infrared beam device
used by many Park Services to count trail use, made by
Diamond Traffic:
http://www.diamondtraffic.com/html/volumecounters.html#TTC-4420


Total-Count offers what seems an inexpensive photoelectric
sensor:
http://total-count.com/


And don't overlook eBay for a good price on traffic counters:
http://search.ebay.com/traffic-counter_W0QQsofocusZbsQQsbrftogZ1QQcatrefZC6QQcoentrypageZsearchQQcopagenumZ1QQcoactionZcompareQQfromZR10QQsacatZ-1QQcatrefZC6QQsargnZ-1QQsaslcZ2QQsadisZ200QQfposZQ5AIPQ2FPostalQQftrtZ1QQftrvZ1QQfsopZ1QQfsooZ1

Like this over-the-door entry/exit counter:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=57016&item=7528225833&rd=1&ssPageName=WDVW

Here's a similar product from a retailer, HomeSecurityStore.com
http://www.homesecuritystore.com/detail_pages/ewp202c.htm


Here's a thermic sensor from InfoDev:
http://www.infodev.ca/AN/Building/DT-10AN.shtml


I think that about covers the bases. Let me know if
a link doesn't work, or something is less than clear.


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Additional information may be found from an exploration of
the links resulting from the Google searches outlined below.

Searches done, via Google:

"Traffic counter" "small store"
://www.google.com/search?q=%22Traffic+counter%22+%22small+store%22

"people counter"
://www.google.com/search?q=%22people+counter%22

"store traffic"
://www.google.com/search?q=%22store+traffic%22

"store traffic counter"
://www.google.com/search?q=%22store+traffic+counter%22

Very good and very qucik answer..