Digital hoarding (also known as e-hoarding) is excessive acquisition and reluctance to delete electronic material no longer valuable to the user. The behavior includes the mass storage of digital artifacts and the retainment of unnecessary or irrelevant electronic data. The term is increasingly common in pop culture, used to describe the habitual characteristics of compulsive hoarding, but in cyberspace. As with physical space in which excess items are described as "clutter" or "junk," excess digital media is often referred to as "digital clutter."

Animal hoarding is keeping a higher-than-usual number of animals as domestic pets without ability to properly house or care for them, while at the same time denying this inability. Compulsive hoarding can be characterized as a symptom of mental disorder rather than deliberate cruelty towards animals. Hoarders are deeply attached to their pets and find it extremely difficult to let the pets go. They typically cannot comprehend that they are harming their pets by failing to provide them with proper care. Hoarders tend to believe that they provide the right amount of care for them. The American Society for the Prevention of Cruelty to Animals provides a "Hoarding Prevention Team", which works with hoarders to help them attain a manageable and healthy number of pets.

Digital hoarding stems from a variety of individual traits and habits, corporate conditions, and societal trends:

- Some individuals experience anxiety when faced with disposing of digital items, particularly if they fear losing something important.

- Many digital hoarders don't know how to organize their digital content or aren't in the habit of doing so, and they lack a methodology for determining which content is worth keeping.

- Keeping all of one's digital files requires less time and effort than evaluating and deleting them.

- Many businesses rely on email correspondence for decision-making and formal approvals, so employees are often careful to keep work emails in case they are needed to verify a decision later.

- Data storage devices are now so large and inexpensive that individuals and companies often do not feel the need to save data selectively.

- The widespread availability and rapid dissemination of open content on the Internet makes it easier for users to obtain digital media, which can accumulate more quickly than ever.

- Since digital media do not take up physical space, they're less likely to be perceived as clutter, and users can more easily forget the extent of what they own.

- Unlike many physical items, electronic content does not die or decay on its own; users must consciously choose to delete it.

Compulsive hoarding in its worst forms can cause fires, unsanitary conditions (such as rat and roach infestations), and other health and safety hazards.

Listed below are possible symptoms hoarders may experience:

- They hold onto a large number of items that most people would consider useless or worthless, such as:

- Junk mail, old catalogs, magazines, and newspapers

- Worn out cooking equipment

- Things that might be useful for making crafts

- Clothes that might be worn one day

- Broken things or trash

- "Freebies" or other promotional products

- Their home is cluttered to the point where many parts are inaccessible and can no longer be used for intended purposes. For example:

- Beds that cannot be slept in

- Kitchens that cannot be used for food preparation

- Tables, chairs, or sofas that cannot be used for dining or sitting

- Unsanitary bathrooms

- Tubs, showers, and sinks filled with items and can no longer be used for washing or bathing.

- Their clutter and mess is at a point where it can cause illness, distress, and impairment. As a result, they:

- Do not allow visitors in, such as family and friends, or repair and maintenance professionals, because the clutter embarrasses them

- Are reluctant or unable to return borrowed items

- Keep the shades drawn so that no one can look inside

- Get into a lot of arguments with family members regarding the clutter

- Are at risk of fire, falling, infestation, or eviction

- Often feel depressed or anxious due to the clutter

Compulsive decluttering is a pattern of behavior that is characterized by an excessive desire to discard objects in one's home and living areas. Other terms for such behavior includes obsessive compulsive spartanism. The homes of compulsive declutterers are often empty. It is the antonym of compulsive hoarding.

Compulsive hoarding, also known as hoarding disorder, is a pattern of behavior that is characterized by excessive acquisition and an inability or unwillingness to discard large quantities of objects that cover the living areas of the home and cause significant distress or impairment. Compulsive hoarding behavior has been associated with health risks, impaired functioning, economic burden, and adverse effects on friends and family members. When clinically significant enough to impair functioning, hoarding can prevent typical uses of space, enough so that it can limit activities such as cooking, cleaning, moving through the house, and sleeping. It can also put the individual and others at risk of fires, falling, poor sanitation, and other health concerns. Compulsive hoarders may be aware of their irrational behavior, but the emotional attachment to the hoarded objects far exceeds the motive to discard the items.

Researchers have only recently begun to study hoarding, and it was first defined as a mental disorder in the 5th edition of the DSM in 2013. It was not clear whether compulsive hoarding is a separate, isolated disorder, or rather a symptom of another condition, such as OCD, but the current DSM lists hoarding disorder as both a mental disability and a possible symptom for OCD. Prevalence rates have been estimated at 2% to 5% in adults, though the condition typically manifests in childhood with symptoms worsening in advanced age, at which point collected items have grown excessive and family members who would otherwise help to maintain and control the levels of clutter have either died or moved away. Hoarding appears to be more common in people with psychological disorders such as depression, anxiety and attention deficit hyperactivity disorder (ADHD). Other factors often associated with hoarding include alcohol dependence, paranoid schizotypal and avoidance traits.

In 2008, a study was conducted to determine if there is a significant link between hoarding and interference in occupational and social functioning. Hoarding behavior is often severe because hoarders do not recognize it as a problem. It is much harder for behavioral therapy to successfully treat compulsive hoarders with poor insight about their disorder. Results show that hoarders were significantly less likely to see a problem in a hoarding situation than a friend or a relative might. This is independent of OCD symptoms, as people with OCD are often very aware of their disorder, which suggests a possible association with OCPD where the behavior are ego-syntonic. The opposite condition is compulsive decluttering.

Bibliomania is not to be confused with bibliophilia, which is the usual love of books and is not considered a clinical psychological disorder.

Other abnormal behaviours involving books include book-eating (bibliophagy), compulsive book-stealing (bibliokleptomania), and book-burying (bibliotaphy).

Frank Tallis, a researcher in the topic of love and lovesickness, suggests in his 2005 article that lovesickness occurs when one is “truly, madly, deeply” in love and should be taken more seriously by medical professionals. Similarly, health experts agree that lovesickness has been known to kill and the diagnosis process should be taken more seriously. Symptoms of lovesickness are usually misdiagnosed for various other diseases or mental health issues such as OCD, this is because love sickness is less commonly recognized as a mental health issue in itself even though lovesickness is an extremely common, widespread disease.

Tallis includes a list of common symptoms of love sickness:

- Mania - an abnormally elevated mood or inflated self-esteem

- Depression

- Nausea

- Tearfulness

- Insomnia, which may lead to fatigue

- Lack of concentration

- Loss of appetite or overeating

- Hopelessness and/or helplessness

- Stress - high blood pressure, pain in chest and heart, acute insomnia; sometimes brought on by a "crush"

- Obsessive-Compulsive disorder - Preoccupation and hoarding valueless but superstitiously resonant items

- Psychologically created physical symptoms, such as upset stomach, change in appetite, insomnia, dizziness, and confusion

- Chronic neck pain, body tremors, intrusive thoughts, frequent flashbacks.

- Rapid mood swings

According to Tallis, many symptoms of being lovesick can be categorized under the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders) and the ICD-10 (International Classification of Diseases). Obsessive-Compulsive disorder (OCD) is a symptom of lovesickness because it includes a preoccupation, this would include constantly checking one's cellphone, Facebook, the hoarding of valueless items, etc. A further study conducted by Italian Psychiatrist Donatella Marazitti found that when people fall in love their estimated serotonin levels drop to levels found in patients with OCD, this level is significantly lower than that of an average or healthy person.

Cyberphobia is a concept introduced in 1980, described as a specific phobia expressed as "an irrational fear of or aversion to computers" or more generally, a fear and/or inability to learn about new technologies.

Some forms of cyberphobia may range from the more passive forms of technophobia of those who are indifferent toward cyberspace to the responses of those who see digital technology as a medium of intrusive surveillance; more extreme responses may involve anti-technological paranoia expressed by social movements that radically oppose ‘technological society’ and ‘the New World Order’.

There are different ways that someone could experience cyberphobia. Teachers may experience a form of cyberphobia if they are forced to change their way of teaching. Another way people may experience cyberphobia is if they feel that they are incompetent, or that the new technology is not needed to advance in life, or that they feel that they lack skills for the new age of technology. Another way people may experience cyberphobia is if they feel like they are going to lose control, or the new technology will affect their status in life.

Bibliomania can be a symptom of obsessive–compulsive disorder which involves the collecting or even hoarding of books to the point where social relations or health are damaged.

Trichotillomania is classified as compulsive picking of hair of the body. It can be from any place on the body that has hair. This picking results in bald spots. Most people who have mild Trichotillomania can overcome it via concentration and more self-awareness.

Those that suffer from compulsive skin picking have issues with picking, rubbing, digging, or scratching the skin. These activities are usually to get rid of unwanted blemishes or marks on the skin. These compulsions also tend to leave abrasions and irritation on the skin. This can lead to infection or other issues in healing. These acts tend to be prevalent in times of anxiety, boredom, or stress.

Compulsive behavior is defined as performing an act persistently and repetitively without it necessarily leading to an actual reward or pleasure. Compulsive behaviors could be an attempt to make obsessions go away. The act is usually a small, restricted and repetitive behavior, yet not disturbing in a pathological way. Compulsive behaviors are a need to reduce apprehension caused by internal feelings a person wants to abstain from or control. A major cause of the compulsive behaviors is said to be obsessive–compulsive disorder (OCD). "The main idea of compulsive behavior is that the likely excessive activity is not connected to the purpose to which it appears directed." Furthermore, there are many different types of compulsive behaviors including, shopping, hoarding, eating, gambling, trichotillomania and picking skin, checking, counting, washing, sex, and more. Also, there are cultural examples of compulsive behavior.

The terms compulsive shopping, compulsive buying, and compulsive spending are often used interchangeably, but the behaviors they represent are in fact distinct. (Nataraajan and Goff 1992) One may buy without shopping, and certainly shop without buying: of compulsive shoppers, some 30% described the act of buying itself as providing a buzz, irrespective of the goods purchased.

Research shows that opposition to attitudinal change can gradually give way to acceptance with the passage of time. Attitudinal change towards acceptance may be a slow and even tedious experience for some teachers.

CBD is frequently comorbid with mood, anxiety, substance abuse and eating disorders. People who score highly on compulsive buying scales tend to understand their feelings poorly and have low tolerance for unpleasant psychological states such as bad moods. Onset of CBD occurs in the late teens and early twenties and is generally chronic. CBD is similar to, but distinguished from, OCD hoarding and mania. Compulsive buying is not limited to people who spend beyond their means; it also includes people who spend an inordinate amount of time shopping or who chronically think about buying things but never purchase them. Promising treatments for CBD include medication such as selective serotonin reuptake inhibitors (SSRIs), and support groups such as Debtors Anonymous.

Lovesickness refers to an informal affliction that describes negative feelings associated with rejection, unrequited love or the absence of a loved one. It can manifest as physical as well as mental symptoms. It is not to be confused with the condition of being lovestruck, which refers to the physical and mental symptoms associated with falling in love. The term lovesickness is rarely used in medical or psychological fields.

Many people believe lovesickness was created as an explanation for longings, but it can be associated with depression and various mental health problems.

Digital phobic is an informal phrase used to describe a reluctance to become fully immersed in the digital age for being fearful of how it might negatively change or alter everyday life.

The fast-paced development of the digital world in the twenty-first century has contributed to the digital divide becoming a very real problem for a segment of the population for whom a lack of education of, interest in, or access to digital devices has left them excluded from the technological world and fearful of its growing omnipresence.

Digital phobic is part of a growing dictionary of digital vocabulary exploring the social impact of the technological age. The phrase considers the fears associated with technological evolution and change, and acknowledges the possibility of exclusion as a result of a rising reliance on technology in day-to-day life.

The main observed symptoms of OCPD are (1) preoccupation with remembering past events, (2) paying attention to minor details, (3) excessive compliance with existing social customs, rules or regulations, (4) unwarranted compulsion to note-taking, or making lists and schedules, and (5) rigidity of one's own beliefs, or (6) showing unreasonable degree of perfectionism that could eventually interfere with completing the task at hand.

OCPD's symptoms may cause varying level of distress for varying length of time (transient, acute, or chronic), and may interfere with the patient's occupational, social, and romantic life.

Intermittent explosive disorder or IED is a clinical condition of experiencing recurrent aggressive episodes that are out of proportion of any given stressor. Earlier studies reported a prevalence rate between 1%-2% in a clinical setting, however a study done by Coccaro and colleagues in 2004 had reported about 11.1% lifetime prevalence and 3.2% one month prevalence in a sample of a moderate number of individuals (n=253). Based on the study, Coccaro and colleagues estimated the prevalence of IED in 1.4 million individuals in the US and 10 million with lifetime IED.

Obsessive–compulsive personality disorder (OCPD) is a personality disorder characterized by a general pattern of concern with orderliness, perfectionism, excessive attention to details, mental and interpersonal control, and a need for control over one's environment, at the expense of flexibility, openness to experience, and efficiency. Workaholism and miserliness are also seen often in those with this personality disorder. Persons affected with this disorder may find it hard to relax, always feeling that time is running out for their activities, and that more effort is needed to achieve their goals. They may plan their activities down to the minute—a manifestation of the compulsive tendency to keep control over their environment and to dislike unpredictable things as things they cannot control.

The cause of OCPD is unknown. This is a distinct disorder from obsessive–compulsive disorder (OCD), and the relation between the two is contentious. Some (but not all) studies have found high comorbidity rates between the two disorders, and both may share outside similaritiesrigid and ritual-like behaviors, for example. Hoarding, orderliness, and a need for symmetry and organization are often seen in people with either disorder. Attitudes toward these behaviors differ between people affected with either of the disorders: for people with OCD, these behaviors are unwanted and seen as unhealthy, being the product of anxiety-inducing and involuntary thoughts, while for people with OCPD they are egosyntonic (that is, they are perceived by the subject as rational and desirable), being the result of, for example, a strong adherence to routines, a natural inclination towards cautiousness, or a desire to achieve perfection.

OCPD occurs in about 2–8% of the general population and 8–9% of psychiatric outpatients. The disorder occurs more often in men.

Obsessive–compulsive disorder (OCD) is a mental disorder where people feel the need to check things repeatedly, perform certain routines repeatedly (called "rituals"), or have certain thoughts repeatedly. People are unable to control either the thoughts or the activities for more than a short period of time. Common activities include hand washing, counting of things, and checking to see if a door is locked. Some may have difficulty throwing things out. These activities occur to such a degree that the person's daily life is negatively affected. Often they take up more than an hour a day. Most adults realize that the behaviors do not make sense. The condition is associated with tics, anxiety disorder, and an increased risk of suicide.

The cause is unknown. There appear to be some genetic components with both identical twins more often affected than both non-identical twins. Risk factors include a history of child abuse or other stress inducing event. Some cases have been documented to occur following infections. The diagnosis is based on the symptoms and requires ruling out other drug related or medical causes. Rating scales such as the Yale–Brown Obsessive Compulsive Scale (Y-BOCS) can be used to assess the severity. Other disorders with similar symptoms include anxiety disorder, major depressive disorder, eating disorders, tic disorders, and obsessive–compulsive personality disorder.

Treatment involves counselling, such as cognitive behavioral therapy (CBT), and sometimes medication, typically selective serotonin reuptake inhibitors (SSRIs). CBT for OCD involves increasing exposure to what causes the problems while not allowing the repetitive behavior to occur. While clomipramine appears to work as well as SSRIs, it has greater side effects. Atypical antipsychotics may be useful when used in addition to an SSRI in treatment-resistant cases but are also associated with an increased risk of side effects. Without treatment, the condition often lasts decades.

Obsessive–compulsive disorder affects about 2.3% of people at some point in their life. Rates during a given year are about 1.2% and it occurs worldwide. It is unusual for symptoms to begin after the age of thirty-five, and half of people develop problems before twenty. Males and females are affected about equally. In English the phrase "obsessive–compulsive" is often used in an informal manner unrelated to OCD to describe someone who is excessively meticulous, perfectionistic, absorbed, or otherwise fixated.

Diogenes syndrome, also known as senile squalor syndrome, is a disorder characterized by extreme self-neglect, domestic squalor, social withdrawal, apathy, compulsive hoarding of garbage or animals, and lack of shame. Sufferers may also display symptoms of catatonia.

The condition was first recognized in 1966 and designated Diogenes syndrome by Clark et al. The name derives from Diogenes of Sinope, an ancient Greek philosopher, a Cynic and an ultimate minimalist, who allegedly lived in a large jar in Athens. Not only did he not hoard, but he actually sought human company by venturing daily to the Agora. Therefore, this eponym is considered to be a misnomer, but he is actually a representative existence of self-neglect. Other possible terms are "senile breakdown", "Plyushkin's Syndrome" (after a character from Gogol's novel "Dead Souls"), "social breakdown" and "senile squalor syndrome". Frontal lobe impairment may play a part in the causation (Orrell et al., 1989).

Pyromania is characterized by impulsive and repetitive urges to deliberately start fires.

Because of its nature, the number of studies performed for fire-setting are understandably very few. However studies done on children and adolescents suffering from pyromania have reported its prevalence to be between 2.4%-3.5% in the United States. It has also been observed that the incidence of fire-setting is more common in juvenile and teenage boys than girls of the same age.

Perhaps the strongest psychological model put forward to explain animal hoarding is obsessive–compulsive disorder (OCD). An overwhelming sense of responsibility for something is characteristic of people with OCD, who then take unrealistic measures to fulfill their perceived duty. Animal hoarders often feel a strong sense of responsibility to take care of and protect animals, and their solution—that of acquiring as many animals as they possibly can—is unrealistic. Further, the hoarding of inanimate objects, practiced by a majority of animal hoarders, is a fairly common occurrence in people with OCD. These connections between animal hoarding and obsessive–compulsive disorder suggest that OCD may be a useful model in explaining animal hoarding behavior. However, this theory has also been refuted by some; Dr. Akimitsu Yokoyama theorizes that animal hoarding could be explained using Asperger syndrome.

Greed is an inordinate or insatiable longing for unneeded excess, especially for excess wealth, status, power, or food.

As secular psychological concept, greed is an inordinate desire to acquire or possess more than one needs. The degree of inordinance is related to the inability to control the reformulation of "wants" once desired "needs" are eliminated. Erich Fromm described greed as "a bottomless pit which exhausts the person in an endless effort to satisfy the need without ever reaching satisfaction." It is typically used to criticize those who seek excessive material wealth, although it may apply to the need to feel more excessively moral, social, or otherwise better than someone else.

The purpose for greed, and any actions associated with it, is possibly to deprive others of potential means (perhaps, of basic survival and comfort) or future opportunities accordingly, or to obstruct them therefrom, thus insidious and tyrannical or otherwise having negative connotation. Alternately, the purpose could be defense or counteraction from such dangerous, potential negotiation in matters of questionable agreeability. A consequence of greedy activity may be inability to sustain any of the costs or burdens associated with that which has been or is being accumulated, leading to a backfire or destruction, whether of self or more generally. So, the level of "inordinance" of greed pertains to the amount of vanity, malice or burden associated with it.