Probably the most useful way to categorize sex toy materials are as "non-porous" or "porous." 

The advantage of a non-porous material--such as 100% silicone, glass, hard plastic, or metal--is that bacteria can not accumulate in microscopic pores in the material and cause infections when reused, so it is safe to use a non-porous toy without a condom if you clean it well between each use.  If your non-porous toy has no motors/vibrators you can often clean them in the top rack of your dishwasher, though you should read the directions provided with each toy.  You can sometimes boil or bleach (with a 10% bleach solution) non-porous toys, and you can always wash with soap and water or an anti-bacterial toy cleaner.  Non-porous materials tend to be sturdier and--with the exception of hard plastic--more expensive than porous materials; therefore some of the toys made from 100% silicone, glass, and metal are the best of the best.

Porous materials, as the name suggests, have microscopic pores in which bacteria can accumulate over time, so it is best to use a condom or other barrier each time you use a porous toy.  For most people, using a condom is no inconvenience because condoms make clean-up easier.  If you choose not to use a condom, make sure each toy has a specific use.  For example, a porous toy should not be used anally and then vaginally, even if washed in between.  These toys cannot go into the dishwasher and cannot be boiled or bleached, so wash carefully with soap and warm water or an anti-bacterial toy cleaner after each use, even if you have used a condom.  The great advantage of porous materials is that they are relatively inexpensive, so it is fairly easy to try something new.

Non-Porous Materials

100% SILICONE

Sex toys made from 100% silicone are often favorites of experienced sex toy users because they are the only non-porous toys that are also flexible.   They are easy to sterilize, phthalate-free and non toxic. 

A NOTE ON SILICONE: Because the labeling of sex toy materials is not regulated, a label can read "silicone" when it is actually a blend of silicone with some other material.  A silicone blend, unlike 100% silicone, is porous rather than non-porous.  If it doesn't say "100% Silicone" or "Medical-Grade Silicone" on the label, it may be a silicone blend.  When buying any toy labeled "silicone," make sure to carefully read the directions for cleaning and care.

Care and Maintenance:  Store silicone toys so that they do not touch other toys, and use water or oil-based lubes--rather than silicone lubes-- with silicone toys.   Whether a toy is 100% silicone or a silicone blend, you can wash with soap and water or an antibacterial toy cleaner.  If your silicone toy is 100% silicone, you can also sterilize with a 10% bleach solution, and boil or wash in the top rack of the dishwasher if there is no motor or other openings.   

Examples:  Silicone Ripple Butt Plug                        Feeldoe Slim Dildo

GLASS

Glass toys seem somehow decadent because they are both beautiful and sexy.  Because of hard, smooth quality of class, they can provide firm pressure to g-spots and p-spots (prostate).  They also react well to being heated or cooled to the user's preference.  Like 100% silicone they are easy to sterilize, phthalate-free and non toxic.

Care and Maintenance: Store your glass toys carefully so that they do not break, and examine your toy carefully before each use to make sure there are no chips or cracks.  High-end glass toys are often made of shatter-proof glass, but cracks and chips can still form in the glass if they toy is dropped or jostled against other hard objects.  If you discover a crack or chip, you must not use your toy because of the risk breaking the toy completely and cutting yourself during play.  Glass toys rarely have motors, so they can often be boiled or put in the top rack of the dishwasher for cleaning. 

Examples:  Sinclair Institute Select Onyx Glass Wand                 Cobalt Duchess Glass Sex Wand

METAL

Various metals, such as aluminum and stainless steel, create classy, sexy toys.  Like 100% silicone and glass, they are non-porous, non-toxic, hypoallergenic and phthalate-free.  Warm them under warm running water or by holding them in your hand, or use cool for an extra sensation.

Care and Maintenance: Use antibacterial toy cleaner or a 10% bleach solution to clean metal vibrators. Metal toys without motors may be boiled or washed in the top rack of the dishwasher.  Store wrapped in a pouch or sock.

Examples:   NJoy Pure Anal Plug Medium             NJoy Fun Wand

HARD PLASTIC (ABS, Acrylic)

Though hard plastic is non-porous, polymer physicist Brent Neal, Ph.D. tells us that hard plastic toys "may have texture due to the molding process that can collect (bacteria). That isn't an issue that's specific to a particular plastic, but rather to the quality and type of mold being used."  When you buy a hard plastic toy, visually and tactilely (with your fingers) examine your toy for places--such as seams--where bacteria might accumulate.  If your toy has such nooks and crannies, you may want to use a condom when you play with your toy.  Hard plastic sex toys come in a wide array of colors and tend to be most often seen in toys designed for external use, such as electric massagers and clitoral stimulators.  They are smooth and firm in texture, though some may have molded seams which may feel slightly rough.  Waterproof toys are often made of hard plastic.   Plastic is phthalate-free and hypoallergenic.

Care and Maintenance: Clean using warm water and soap and an antibacterial sex toy cleaner.  Most hard plastic toys have motors for vibrators, but if your toy has no motor, you may be able to wash it on the top shelf of your dishwasher.  Can be stored touching other toys.  If the toy is a vibrator, remove batteries between each use so that batteries are not drained when not being used. 

EXAMPLES:    Natural Contours Ultime Vibrator          G-Gasm Delight Vibrator

Porous Materials

ULTRA-REALISTIC

Cyberskin® ,UR3®, PleasureSkin® and other ultra-realistic materials are used in dildos and dongs as well as masturbators.  They ultra-realistic, meaning they mimic human skin and often contain PVC, TPE, or similar materials.   They warm just as real skin does and are just as elastic and malleable. Ultra-realistic materials  toys do require a bit of extra care, and the manufacturers recommend using only water-based lubricants, as silicone and oil-based lubricants will break these materials down over time.  Ultra-realistic substances are also extremely porous, so we strongly recommend using condoms with each use.  Some are phthalate-free; others may contain phthalates.

Care and Maintenance:    Wash thoroughly with antibacterial soap or toy cleaner after each use; once it is totally dry apply cornstarch or Cyberskin Renew Powder (not talc) to the toy.  This will keep its realistic, supple feel and appearance.   Store in a zip-lock bag or sock in a cool, dark place, not touching other toys.

EXAMPLES:     Cyberskin Slimline Realistic Dildo      Mister Marcus' Personal Fluffer

JELLY RUBBER 

Jelly Rubber toys are made of a very soft, pliable material which often contain phthalates and/or latex, so we suggest using a condom with your jelly toys. Use water-based lubricants with these toys as well..

Care and Maintenance:  Clean thoroughly with soap and water or antibacterial toy cleaner.  Store so they do not touch any other toys.

Examples: Pink Ice Jelly Dong                 Eden Pleasure Petals

TPR – Thermo Plastic Resin

This is a lightweight material that’s strong yet pliable.  Though it is similar in texture to jelly rubber, it’s phthalate-free and easily washable.  

Care and Maintenance:  Clean thoroughly with soap and water or antibacterial toy cleaner.  Store so they do not touch any other toys.

EXAMPLES: Adonis Extension Sleeve                               Evolved Bendable Flexems Flame

TPE – Thermo Plastic Elastomer

TPE is soft, flexible, and durable.  It is hypoallergenic, phthalate-free and non-toxic. 

Care and Maintenance: Clean thoroughly with soap and water or antibacterial toy cleaner.  Store so they do not touch any other toys.

Examples: Glow in the Dark Palm Pal                      Evolved Romantic G

PVC – Polyvinyl Chloride

PVC is a plastic polymer which may or may not contain phthalates.