An access counter will give you an estimate on the amount of traffic (visitors) your page has had. Access counters are usually a graphic odometer. Counters are not always accurate, because if someone visits your page in a text browser such as Lynx, or with graphics loading turned off, their visit will not increment (add 1) your counter. Also, if a visitor hits the reload button, your access counter will increment by one. To add a counter to your page, the place you get the counter from will give you a few lines of HTML code to paste into your page where you want the counter to appear.
The most reliable counter will come from your home page hoster if they offer one. If your page is hosted by your ISP, contact them to see if they offer a free counter to you. If your page is located on a free hoster, they may offer a free counter to you also...
Many other hosts offer free counters... be sure to check out the help/FAQ of their site. If your web host does not provide a free counter, or you wish to get a free counter from elsewhere, you have a few other options. One of them used to be Digits.com, but they recently shut down new counter requests because their servers were overloaded. Also, CyberHits, which I formerly recommended as a counter, has shut down its servers. If you still need to find a counter outside your home page provider, you should find a few good options on the Web Page Access Counters and Trackers Page @ markwelch.com.
The control panels for my recommended hosts offer free counters to for you to add to your site.
Guestbooks help you to know who is visiting your site, and what their comments are about it. When you view your guestbook, it will show anyone that has signed it. When someone signs your guestbook, they usually have options to put their name, email address, home page url, where they found your page from, where they live, and any comments they have about your page.
Over the past, Lpage.com has been slow at serving guestbooks, but recently they have increased capacity and are again my recommended guestbook server. When your create your guestbook, you will receive the HTML code to cut and paste into your page. Another place to consider is Alxbook.com.